University of Tennessee, Knoxville TRACE: Tennessee Research and Creative Exchange
Doctoral Dissertations Graduate School
8-1991
Pregnant and Postpartum Adolescents' appetite Compulsions, Food Preferences, and Reasons for Dietary Change
Janet Faye Pope University of Tennessee, Knoxville
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Recommended Citation Pope, Janet Faye, "Pregnant and Postpartum Adolescents' appetite Compulsions, Food Preferences, and Reasons for Dietary Change. " PhD diss., University of Tennessee, 1991. https://trace.tennessee.edu/utk_graddiss/3771
This Dissertation is brought to you for free and open access by the Graduate School at TRACE: Tennessee Research and Creative Exchange. It has been accepted for inclusion in Doctoral Dissertations by an authorized administrator of TRACE: Tennessee Research and Creative Exchange. For more information, please contact [email protected]. To the Graduate Council:
I am submitting herewith a dissertation written by Janet Faye Pope entitled "Pregnant and Postpartum Adolescents' appetite Compulsions, Food Preferences, and Reasons for Dietary Change." I have examined the final electronic copy of this dissertation for form and content and recommend that it be accepted in partial fulfillment of the equirr ements for the degree of Doctor of Philosophy, with a major in Human Ecology.
Jean D. Skinner, Major Professor
We have read this dissertation and recommend its acceptance:
Betty R. Carruth, Carol A. Costello, Edward T. Howley
Accepted for the Council:
Carolyn R. Hodges
Vice Provost and Dean of the Graduate School
(Original signatures are on file with official studentecor r ds.) To the Graduate Council:
I am submitting herewith a dissertation written by Janet Faye Pope entitled "Pregnant and Postpartum Adolescents' Appetite Compulsions, Food Preferences, and Reasons for Dietary Change". I have examined the final copy of this dissertation for form and content and recommend that it be accepted in partial fulfillment of the requirements for the degree of Doctor of Philosophy, with a major in Human Ecology.
�Lil_�-� J n D. Skinner Major Professor
We have read this dissertation and recommend its acceptance:
�a-tqR.. � �A-�
Accepted for the Council:
Associate Vice Chancellor and Dean of The Graduate School Pregnant and Postpartum Adolescents' Appetite
Compulsions, Food Preferences, and
Reasons for Dietary Change
A Dissertation
Presented for the
Doctor of Philosophy
Degree
The University of Tennessee, Knoxville
Janet Faye Pope
August 1991 ACKNOWLEDGEMENTS
The author wishes to express gratitude and appreciation to the many people who were instrumental in the completion of this work. I would like to thank my major professor, Dr. Jean Skinner, and the other members of my committee, Dr. Betty Ruth Carruth, Dr. Carol Costello, and Dr. Ed Howley, for their time, their guidance, and their support.
A special thanks goes to the graduate students who worked on this project with me, Lisa Varner, Dena Goldberg, Wina Nevling, Joni Pierson, and Brenda
Stephens, for their assistance, understanding, and friendship.
I would like to thank the Department of Nutrition and the Agricultural
Experiment Station for the financial assistance I received. I also am grateful to
John Schneider and Dr. William Sanders for sharing their time and statistical expertise. I express my sincere appreciation to the Department of Nutrition support staff, especially Judy Loveday and Kathy Dalton, for their contributions.
Thanks also to my typist, Marylenna Honeycutt.
I express loving appreciation to my family and friends for their encouragement and support. I am especially indebted to my parents, Betty and
Robin Pope, for their faith, their understanding, and their love. I also wish to thank my grandfather, B. Ford Pope, for always believing in me; it is in his memory that this dissertation is dedicated.
11 Abstract
This study was conducted to examine factors influencing the nutritional habits of adolescents during and after pregnancy. Data were collected on 97 white adolescents during the third trimester of pregnancy, and on 64 of the same adolescents at one year postpartum. The study included three components: (a) an exploration of reported changes in eating habits and reasons for the changes;
(b) a semi-structured interview used to obtain information about appetite compulsions (cravings, aversions, and pica); and (c) a sensory analysis of preferences for 16 specific foods.
Data showed that adolescents made positive changes in their diets during pregnancy; 64% reported eating more food, and over half reported increased intakes of milk and dairy products, fruits and vegetables, and breads and cereals.
Reasons for dietary change included both endogenous (physiological) and exogenous factors. Most of the adolescents experienced cravings and aversions during pregnancy. Foods reported as craved most often included sweets, especially chocolate, ice cream, fresh fruits and juices, pickles, pizza, and fast foods. Aversions were most often reported to eggs, meats, and pizza.
Adolescents indicated that cravings led to increased intake, and aversions resulted in decreased food consumption. Based on sensory analysis, the pregnant adolescents preferred whole over skim milk, and salted chips, nuts, and crackers
111 over the low-salt/unsalted varieties; they did not prefer ice cream over ice milk or yogurt.
Postpartum adolescents indicated several changes in dietary habits after pregnancy. Consumption of dairy products and fruits and vegetables often were reported to be lower than during pregnancy, and consumption of fast foods, sodas, and spicy foods were higher. Although rates were reportedly lower, appetite compulsions did occur during the first year postpartum. Analysis of the sensory data showed that preferences for whole and skim milk were higher during the last trimester of pregnancy than one year later. No other differences between pregnancy and postpartum food preferences were identified.
The average diet consumed by the pregnant adolescents met or exceeded the RDAs for all nutrients except iron, folate, vitamin D, vitamin B6, magnesium, and selenium. At 12 months postpartum, mean intakes of energy and all nutrients were lower; nutrient density was lower; and greater numbers of postpartum adolescents consumed diets that did not meet the RDA for each nutrient.
IV TABLE OF CONTENTS
CHAPTER PAGE
I. INTRODUCTION ...... 1 The Problem ...... 1 Appetite Compulsions ...... 3 Food Preferences ...... 5 Overview of Study ...... 6 Research Questions ...... 7 Limitations ...... 9 Assumptions ...... 10
II. REVIEW OF LITERATURE ...... 11 Adolescent Pregnancy ...... 11 Outcome ...... 11 Growth During Adolescent Pregnancy ...... 14 Weight Gain in Adolescent Pregnancy ...... 16 Nutritional Requirements of Pregnant Adolescents ...... 17 Eating Habits of Pregnant Adolescents ...... 19 Nutritional Status of Pregnant Adolescents ...... 20 Factors Affecting Food Intake During Pregnancy ...... 20 Educational Level and Nutrition Knowledge ...... 21 Prenatal Education ...... 22 Nutrition Supplementation ...... 23 Appetite Compulsions ...... 23 Dietary cravings ...... 24 Pica ...... 26 Aversions ...... 29 Beliefs ...... 31 Changes in Taste Sensitivity ...... 34 Sweet taste ...... 35 Salty taste ...... 35 Sour and bitter tastes ...... 36 Hormones and taste sensitivity ...... 37 Food Preferences ...... 40 Relationship Between Taste and Preference ...... 41 Sensory Evaluation ...... 44 Sensory evaluation techniques ...... 44 The physical environment ...... 48 Postpartum Adolescents ...... 50 Summary ...... 50
V III. METHODOLOGY ...... 55 Overview ...... 55 Human Subjects Approval ...... 55 Selection Criteria and Recruitment ...... 56 Incentives for Participation ...... 57 Instrument Development ...... 59 Data Collection ...... 61 Phase One: During Pregnancy ...... 62 Informed consent and demographic and background data ...... 62 Dietary data ...... 63 Changes in food consumption patterns and reasons for change ...... 63 Appetite compulsions and beliefs about appetite compulsions ...... 64 Food Preferences ...... 65 Phase Two: Postpartum ...... 67 Demographic and background data ...... 67 Dietary data ...... 67 Changes in food consumption patterns and reasons for change ...... 68 Appetite compulsions ...... 69 Food Preferences ...... 69 Data Analysis ...... 70 Demographic and Background Data ...... 70 Dietary Data ...... 71 Changes in Food Consumption Patterns and Reasons for Change ...... 72 Appetite Compulsions ...... 73 Beliefs About Appetite Compulsions ...... 73 Food Preferences ...... 74
IV. RESULTS AND DISCUSSION ...... 75 Description of Sample ...... 75 Demographic and Background Characteristics of Pregnant Adolescents ...... 78 Demographic and Background Characteristics of Postpartum Adolescents ...... 82 Dietary Data ...... 85 Dietary Intake of Pregnant Adolescents ...... 85 Dietary Intake of Postpartum Adolescents ...... 89 Comparison of Diets During and After Pregnancy . . . . . 90
VI Dietary Changes ...... 93 Reported Changes in Food Consumption During Pregnancy ...... 93 Reported Reasons for Dietary Change During Pregnancy ...... 96 Reported Changes in Food Consumption After Pregnancy ...... 110 Reported Reasons for Dietary Change After Pregnancy ...... 112 Appetite Compulsions ...... 124 Pregnancy-associated Cravings and Aversions ...... 124 Beliefs About Pregnancy-associated Dietary Cravings ...... 130 Relationships Between Appetite Compulsions and Dietary Intake ...... 133 Postpartum Appetite Compulsions ...... 134 Food Preferences ...... 137 Food Preference Scores of Pregnant Adolescents ...... 138 Food Preference Scores of Postpartum Adolescents . . . . 142
V. CONCLUSIONS AND IMPLICATIONS ...... 145 Implications for Health· Care Providers ...... 150 Research Needs ...... 151
REFERENCES ...... 154
APPENDICES ...... 172
A. Recruitment Tools ...... 173
B. Recruitment Letters ...... 175
C. Letter of Confirmation for Appointments ...... 177
D. Three Month Follow-up Survey ...... 178
E. Copy of Letter Sent to Subjects at 10 Months Postpartum ...... 179
F. Statement of Informed Consent ...... 180
G. Information Form ...... 181
H. Demographics and Background Information 182
vii I. Food Recall/Record Form 183
J. Food Frequency Checklist 186
K. Appetite Changes Interview Form ...... 188
L. Beliefs About Appetite Compulsions ...... 189
M. Incomplete Block Design for Sensory Analysis ...... 191
N. Food Preference Analysis Evaluation Form ...... 196
0. Postpartum Cravings and Aversions Interview Form ...... 198
P. Additional Dietary Data ...... 199
VITA ...... 204
Vlll LIST OF TABLES
TABLE PAGE
1. Recommended Dietary Allowances forPregnancy ...... 18
2. Recommended Dietary Allowances for Female Adolescents ...... 51
3. Disposition of Pregnant Adolescents Contacted to Participate in the AES-TN860 Study ...... 76
4. Follow-up of Pregnant Adolescents at Twelve Months Postpartum ...... 77
5. Number of Adolescents Completing Specific Components of Research Study AES-TN860 During and After Pregnancy ...... 79
6. Demographic and Background Characteristics of Pregnant Adolescents . :· ...... 80 7. Demographic and Background Characteristics of Postpartum Adolescents ...... 83
8. Mean Dietary Intake and Percent of RDA for 97 Pregnant Adolescents ...... 86
9. Average Daily Nutrient Intake of Pregnant Adolescents in AES-TN860 Compared to Nutrient Intake of Pregnant Adolescents in Other Studies: Percentage of 1989 Recommended Dietary Allowances ...... 88
10. Mean Dietary Intake and Percent of RDA for 57 Postpartum Adolescents ...... 91
11. Comparison of Adolescents' Dietary Intake During the Third Trimester of Pregnancy and at Twelve Months Postpartum ...... 92
12. Adolescents' Self-reported Changes in Usage Patterns for Selected Food and Non-food Items During Vs. Prior to Pregnancy ...... 94
lX 13. Adolescents' Endogenous and Exogenous Reasons for Increasing Consumption of Specific Foods and Usage of Selected Non-food Items During Pregnancy . .. . . 98
14. Adolescents' Endogenous and Exogenous Reasons for Decreasing Consumption of Specific Foods and Usage of Selected Non-food Items During Pregnancy ...... 104
15. Adolescents' Self-reported Changes in Usage Patterns for Selected Food and Non-food Items Postpartum Vs.During Pregnancy ...... 111
16. Adolescents' Endogenous and Exogenous Reasons for Increasing Consumption of Specific Groups of Food and Usage of Selected Non-food Items Following Pregnancy 113
17. Adolescents' Endogenous and Exogenous Reasons for Decreasing Consumption of Specific Groups of Food and Usage of Selected Non-food Items Following Pregnancy 118
18. Number of Cravings and Aversions Reported by Adolescents During and After Pregnancy ...... 125
19. Dietary Cravings Reported by 97 Pregnant Adolescents ...... 126
20. Dietary Aversions Reported by 97 Pregnant Adolescents ...... 129
21. Pregnant Adolescents' Responses to Belief Statements About Cravings During Pregnancy 131
22. Dietary Cravings Reported by 64 Adolescents at 12 Months Postpartum ...... 136
23. Minimum and Maximum Food Preference Scores of Adolescents During the Third Trimester of Pregnancy and at Twelve Months Postpartum ...... 139
24. Comparison of Paired Food Scores During the Third Trimester of Pregnancy and at Twelve Months Postpartum ...... 140
X 25. Comparison of Adolescents' Food Preference Scores Obtained During the Third Trimester of Pregnancy and at Twelve Months Postpartum ...... 143
XI CHAPTER 1
INTRODUCTION
The Problem
Adolescent pregnancy is a common occurrence in American society.
According to the National Center for Health Statistics (1), in 1988, over 322,000
live infants were born to adolescents 18 years old and younger; approximately
312,000 were born to mothers who were between the ages of 15 and 18 at
delivery, and approximately 10,600 were born to mothers less than 15 years of age.
In Tennessee, 7,796 live births to mothers 15 to 18 years of age and 316 to
younger adolescents were reported (1 ).
It is generally accepted by most health professionals that pregnant adole�cents are tlat risk" (1 -12). The incidence of maternal and infant morbidity and mortality is higher in adolescents than in adult women (13-17); pregnant adolescents are more likely than adults to deliver prematurely ( <37 weeks), and
they are also more likely to deliver low-birth weight infants ( < 2500 grams) (2, 3,
17-19). Adolescents frequently enter pregnancy at lower weight for height ratios
than do adults, and as such require larger weight gains to produce infants of
optimal or average newborn sizes (3, 11, 15, 20).
1 Historically, the increased risk to adolescents during pregnancy has been attributed to physiological/biological immaturity. More recent data suggest that except for the very young, the risk is probably due more to environmental than physiological factors (5, 10, 12, 21-26). "Nutritional status is considered one of the most important environmental factors affecting the health of the teenage mother and her fetus" (5, p.1).
Determination of the nutritional requirements of the pregnant adolescent traditionally has been based on the premise that the nutritional cost of pregnancy must be superimposed upon the increased energy and nutrient needs of adolescent growth and development (27). This assumption resulted in Recommended
Dietary Allowances (RDA) that were higher for pregnant adolescents than for any other age and sex group. The current recommendations for pregnant adolescents, with the exception of energy, do not differ from those made for pregnant adults
(28). The suggested requirement for most nutrients, however, is higher during than prior to pregnancy.
Pregnant adolescents frequently have been shown to consume diets that provide inadequate amounts of iron, calcium, folate, zinc, and vitamin B6 ( 6, 29-
32). Additionally, in any group studied, there are some adolescents who fail to meet the requirements for energy, the B-complex vitamins, ascorbic acid, and vitamin A.
To date, research in the area of nutrition and adolescent pregnancy has focused on the outcome, or on the infant. There is a definite need for research
2 which places emphasis on the adolescent herself: What does she eat? Why does she eat what she does? And, what factors influence her decisions about diet? In a recent report by the Food and Nutrition Board of the National Academy of
Sciences (33), the Subcommittee on Dietary Intake and Nutrient Supplements
During Pregnancy expressed a need for additional research "to determine the intakes of nutrients by pregnant teenagers in specific age and economic groups"
(p. 21). This committee also cited a need for "investigating the nutritional consequences of ... food cravings and aversions ... " (p. 21).
Appetite Compulsions
Appetite compulsion is the generic term used to describe cravings, aversions, and pica. Most women experience appetite compulsions at some time during pregnancy; reported occurrence rates range from 66 to 85% (34-39).
Foods most commonly craved by pregnant women include sweets, fruits and fruit juices, dairy products, and salty foods (34, 35, 37-39). Some women also report cravings for and consumption of non-food items such as clay, laundry starch, ice, and dirt (34, 40, 41). The incidence of non-food cravings is not known, although it has been suggested that the prevalence of pica (consumption of non-food substances) among black women, women from rural areas, and women with a family history of pica has remained steady since the 1970's ( 41). Dietary aversions apparently occur earlier in the pregnancy than do cravings and are frequently reported as being more severe (37). The most common pregnancy-associated
3 aversions appear to be to alcohol, coffee, Italian foods, meats, and eggs (34, 35,
37-39).
It has been suggested that appetite compulsions affect consumption of specific foods during pregnancy (37). Cravings for specific foods are thought to
lead to increased intake, whereas aversions more likely result in decreased
consumption, or in some cases, avoidance.
Researchers have suggested that pregnant women make other changes in
their diets on the basis of their beliefs about nutrition during pregnancy (42-45).
While some beliefs are supported by science, others are based on myths,
superstitions, and old wives' tales. According to Carruth and Skinner (46), beliefs
about dietary cravings during pregnancy persist, especially in the southeastern
United States. The effects such beliefs actually have on dietary intake is not known.
To date, research in the area of pregnancy-associated appetite compulsions has focused on adult populations. Neither the percentage of adolescents experiencing cravings and aversions during pregnancy, nor the nature of such cravings and aversions have been described previously. Adolescents' beliefs about
dietary cravings and the relationship among beliefs, cravings, and dietary intake also has not been published previously.
4 Food Preferences
Women frequently report changes in food preferences during pregnancy; sometimes they report liking a food that was previously disliked, and other times they express dislike for a previously enjoyed food. Some preference changes may occur as the result of changes in taste perception ( 47-49). However, some women indicate that their preference changes are due to psychological factors (34, 50).
Therefore, it is obvious that changes in taste sensitivity cannot explain all changes in the food preferences of pregnant women.
Food preference and taste are not synonymous. Food preference is a complex reaction, influenced by a large number of psychological and physiological variables (51-53). The taste mechanism is a physiological factor which affects preference (53). In other words, taste is one part of preference.
There is some evidence that changes in sensitivity, especially for sweet and salty tastes, occur with pregnancy, and that preferences for these tastes also change (47-49, 54). These findings are based on studies using chemical solutions rather than actual foods. There is no evidence to indicate that sensitivity to tastes in solution is related to preference for specific foods during pregnancy. Also, there is no evidence to suggest that adolescents' food preferences change during pregnancy.
5 Overview of Study
This research was conducted as part of a larger study of the nutritional
habits of adolescents during and after pregnancy. The overall study (AES-TN860)
was funded by the Agricultural Experiment Station at The University of Tennessee
Institute of Agriculture. The overall objective was to identify dietary behaviors
and social factors of adolescents which influence nutritional health during
pregnancy and the following 12 months ( 55). Five doctoral students, one Master
of Science student, and two nutrition faculty were involved in the study; each
evaluated the influences of different dietary and social factors. An analysis of the
effect of television, parents, and peers on food choices of pregnant adolescents has
been published ( 56); additional evaluations are being conducted on the effects of
beliefs about nutrition during pregnancy, peer influences during and after
pregnancy, weight history and dieting patterns before and after pregnancy, and
infant feeding practices of adolescent mothers.
The purposes of this portion of the study were (a) to determine changes in
food consumption patterns that occur with pregnancy and to evaluate reasons for
those changes; (b) to determine changes in food consumption patterns that occur
in the first year following delivery and to evaluate reasons for the changes; ( c) to
evaluate the effect of appetite compulsions ( dietary cravings, non-food cravings,
and aversions) on dietary intake during and after pregnancy; and ( d) to compare food preferences during and after pregnancy.
6 Data were collected during the third trimester of pregnancy and again at 12
months postpartum. Data collection techniques included personal semi-structured
interviews and sensory analysis of specific foods. Ninety-seven adolescents were
interviewed during pregnancy, and 64 completed the follow-up analysis at one year
postpartum.
Research Questions
This study was designed to answer the following research questions:
1. What dietary changes do adolescents report making during pregnancy, and
why do they make the changes?
a. How does consumption of specific foods during pregnancy compare to
consumption of the same foods prior to pregnancy?
b. What reasons do adolescents give for increasing consumption of
specific foods during pregnancy?
c. What reasons do adolescents give for decreasing consumption of
specific foodsduring pregnancy?
d. Which dietary changes are the result of endogenous (physiological)
factors and which are the result of exogenous variables?
2. What effects do appetite compulsions have on the dietary intake of pregnant
adolescents?
a. How common are appetite compulsions in pregnant adolescents?
7 b. What foods, beverages, and non-food substances are craved most often,
and what are the most frequently reported dietary aversions?
c. At what stage of pregnancy do appetite compulsions appear and how
long do they last?
d. What is the relationship between appetite compulsions and beliefs
about appetite compulsions?
e. What is the relationship between specific appetite compulsions and
dietary intake?
3. What dietary changes do adolescents report making postpartum, and why do
they make these changes?
a. How does consumption of specific foods after pregnancy compare to
consumption of the same foods during pregnancy?
b. What reasons do adolescents give for increasing consumption of
specific foods?
c. What reasons do adolescents give for decreasing consumption of
specific foods?
d. Which dietary changes are the result of endogenous factors, and which
are the result of exogenous variables?
4. What effects do appetite compulsions have on dietary intake of adolescents
at 12 months postpartum?
a. How common are appetite compulsions in postpartum adolescents?
b. What are the most frequently reported cravings and aversions?
8 c. What is the relationship between specific appetite compulsions and
dietary/nutritional intake?
5. How do food preferences, assessed by sensory analysis, during pregnancy
compare with food preferences at 12 months postpartum?
a. During pregnancy, are there differences in preference scores for high
and low-fat foods? for high- and low-sugar foods? for high- and low
salt foods?
b. At 12 months postpartum, are there differences in preference scores
for high- and low-fat foods? for high- and low-sugar foods? for high
and low-salt foods?
Limitations
As with any research study, there are limitations to this investigation. First, subjects were not randomly selected; all were volunteers who lived within a 120- mile radius of Knoxville, Tennessee. Second, deliberate decisions about selection criteria necessitated exclusion of all except white adolescents who were between
28 and 35 weeks gestation. Most participants were from low socioeconomic groups. Therefore, this sample may be representative only of low-income, white, pregnant adolescents in East Tennessee. Third, follow-up at 12 months postpartum was voluntary and was limited to those adolescents who could be located. Because follow-up was less than 100%, it is possible that the adolescents
9 not completing the study were different at 12 months postpartum than those who did complete the study. Fourth, much of the data collected were self-reported data, and therefore may be subject to bias.
Assumptions
In conducting this research, certain assumptions were made by the investigator. The first assumption was that pregnant adolescents were capable of providing the information we sought to collect. The second assumption was that the participants were honest in their responses. The third assumption was that the four days of dietary data were representative of the adolescents' usual dietary intake. The fourth assumption was that external biases due to the interviewer and the data collection environment were constant for all participants.
10 CHAPTER II
REVIEW OF LITERATURE
Adolescent Pregnancy
It generally is accepted by most health professionals that adolescents are
"at risk" during pregnancy (1-12). Historically, the risk has been attributed to biological immaturity, although today environmental factors, including nutrition, are believed to be at least as important and possibly more so (5, 10, 12, 21-26).
Outcome
Many factors, including prenatal health care (33, 57-60), nutritional status
(33, 61-65), use of alcohol, tobacco, and drugs (33, 66-70), and gestational weight gain (33, 71-78), influence the outcome of pregnancy. Maternal age has been identified as another factor with the potential to affect both maternal and infant outcomes. In general, research has shown that adolescents are more likely than adults to deliver prematurely ( <37 weeks gestation), and they also are more likely to deliver low birth weight infants ( <2500 grams) (1-3, 17-20).
Several researchers have studied adolescent pregnancies in an effort to determine whether the risk is due to age per se or whether the risk is due to other
11 factors related to age. In one study, Zlatnik and Burmeister (19) reviewed medical records of adolescents 17 years of age and younger to determine if age was related to obstetric risk. As expected, the younger compared to older adolescents had a higher incidence of low birth weight. However, the researchers found that low gynecological age (GA - the difference between chronological age and the age at menarche) was a better measure of potential risk than was low chronological age. The researchers suggested that a low GA might predispose premature emptying of the uterus; since it had fewer complete cycles, the uterus might be structurally or functionally less able to carry a fetus to term.
Felice and co-workers (79) found that compared to older adolescents, the chronologically younger adolescents had a higher incidence of premature rupture of membranes but had no higher rates of pre-eclampsia, anemia, or labor and delivery problems. They found no significant differences in mean infant birth weight, placental weight, or gestational age in younger and older adolescents, but there was a trend toward more low birth weight infants born to adolescents of low chronological and gynecological ages. Naeye (7) found that immaturity was related to increased risk; he hypothesized that negative outcomes were the result of competition for nutrients between an immature mother and her fetus.
Frisancho and associates (20) also found a higher incidence of low birth weight infants born to adolescent mothers, and they determined that the low birth weight was not due either to short duration of pregnancy or gynecological immaturity. They concluded that due to physical growth, adolescents have greater
12 nutritional requirements than adults, and that the adolescent mother and fetus actually do compete for nutrients.
Other researchers have suggested that there is no competition for nutrients in adolescent pregnancy. For example, in a study of 275 infants born to adolescent mothers and 423 infants born to adults, Zuckerman and associates (10) found that the babies born to adolescent mothers weighed 94 grams less at birth than the babies born to older mothers; however, the adolescents were not at greater biological risk than nonadolescents for poor neonatal outcome. These researchers concluded that factors other than a young age were associated with adverse outcomes.
Horan and co-workers (72) also compared birth weights of infants born to adolescents and those born to older women. They found no significant differences in birth weights between the two groups, but the infants of adolescents weighed slightly more, on the average, than infants of older mothers. They, too, concluded that risk was due not to age, but to sociodemographic characteristics. Geronimus
(22) suggested that any association between adolescent maternity and preterm birth, low birth weight, and neonatal death reflect environmental risk factors rather than biological risk.
Thus, while researchers tend to agree that adolescent mothers and their babies are at greater risk for negative outcomes during pregnancy, they do not necessarily agree on the cause; is risk due to biological factors, environmental factors, or a combination of the two?
13 Growth During Adolescent Pregnancy
Researchers now question whether or not linear growth can be expected during the course of adolescent pregnancy. The reason for this is that at a time when the adolescent is capable of conception, her growth rate and subsequent nutritional needs have declined (80). Post-menarcheal height gain in nonpregnant females averages only about six centimeters or 2.4 inches, spread over a four to five year period (81, 82).
Some investigators have measured actual changes in height during pregnancy. Meserole and associates (83) compared pregravid heights with recorded heights sixmonths later in 80 adolescents aged 13 to 17 years; no significant changes in height were seen, indicating no significant linear growth during pregnancy. In a longitudinal analysis of 1601 adolescents followed through two or three pregnancies, Garn and co-workers (84) found no evidence to support the hypothesis that large weight gains observed in younger adolescents could be attributed to rapid growth. These investigators suggested that only those adolescents who became pregnant in the first year after menarche might be expected to experience significant linear growth during pregnancy.
Another group of researchers (21) compared height and weight of 139 adolescents at the onset of their first and second pregnancies. The younger adolescent primaparas were shorter and weighed less at the time of their first pregnancies than their second pregnancies. The one centimeter differences in
14 height (0.37 cm/year) between the two pregnancies supports the hypothesis that younger adolescents could not be considered fully biologically mature.
Scholl and co-workers (85, 86) used a knee height measuring device to monitor growth during pregnancy. This device measures lower leg length and can detect small amounts of linear growth over short periods of time. In one study,
67% of those adolescents less than 15 years old and 50% of the 15 to 18 year-olds had larger increments in leg length during pregnancy than did the mature controls, and thus appeared to be growing. In a second study, over 55% of 12 to 15 year olds and a smaller percentage of older adolescents grew in knee height during pregnancy. While the absolute value of change was minimal, knee height is only one of several areas that might be expected to change with linear growth. The authors concluded that continuing maternal growth may affect the well-being of both mother and fetus and could be one source of complications associated with young maternal age.
It also has been shown that the birth canal matures more slowly than might be expected. Moerman (23) analyzed growth and development of the pelvic birth canal in 90 adolescents aged 8 to 18. He found that the pelvic basin grew more slowly than stature, that the size of the birth canal was smaller the first three years past menarche than at age 18, and that the pelvis was smaller and less mature among early than late maturers. He concluded that reproductive maturation and attainment of adult height do not indicate completed growth of the pelvic birth
15 canal, and that immaturity of the birth canal may pose significant risks among pregnant adolescents.
While results of these studies are not conclusive, it does appear that those adolescents who become pregnant soon after menarche may be at greater risk of poor obstetric performance and neonatal outcome than are older adolescents and adults. In this group of adolescents, the nutritional needs for growth may actually be compounded with those of normal pregnancy, and fetal-maternal competition for nutrients may occur (7, 20, 85, 86).
Weight Gain in Adolescent Pregnancy
Many researchers have studied the relationship between gestational weight gain and pregnancy outcome, both in adults and in adolescents, yet it still is not possible to state with absolute certainty the precise gain that is optimal for a given individual (87). The incidence of clinical complications does appear to be higher at either extreme, but normal outcome is possible at a wide range of weight changes (88-90).
Researchers have identified no consistent relationship between maternal age and gestational weight gain in American women. Some investigators have reported that adolescents gain more weight during pregnancy than do adults (25,
91 ); others report that adolescents gain less weight (83, 92); still others find no significant differences (31, 72, 79).
16 Prepregnancyweight forheight is a significant determinant of fetal health and birth weight in adult mothers, and it is thought to be even more important in
adolescents (3, 11, 15, 20, 71-78, 93, 94). Current recommendations forweight gain during pregnancy are therefore based on prepregnancyweight. The Food and Nutrition Board Subcommittee on Nutritional Status and Weight Gain During
Pregnancy (33) recommends that women with low weight to height ratios (body mass index, BMI, < 19.8) gain between 28 and 40 pounds; those with normal ratios
(BMI = 19.8 to 26) should gain 25 to 35 pounds; and those with high weight to height ratios (BMI > 26) should gain 15 to 25 pounds. Because the weight gain
associated with an optimal or average newborn weight is greater forthe young (3,
15, 20, 33), the Committee recommends that adolescents aim forthe upper limit of the appropriate range based on weight for height ratios.
Nutritional Requirements of Pregnant Adolescents
The most recent revision of the Recommended Dietary Allowances (RDA) was published in 1989 (28). Based on information available at that time, the requirements were re-evaluated for all age groups and for pregnant and lactating women. For the first time, RDAs during pregnancy were tabulated as absolute figures rather than as additions to the basic allowances; with the exception of energy, the RDAs for pregnant adolescents and for pregnant women do not differ.
The RDAs for pregnancy are summarized in Table 1.
17 Table 1. Recommended Dietary Allowances for Pregnancy.a
Nutrient RDA
Energy (Kcal) +300 Protein (gm) 60 Vitamin A (µgRE) 800 Vitamin D (µg) 10 Vitamin E (mg a -TE) 10 Vitamin K (µg) 65 Ascorbic acid (mg) 70 Thiamin (mg) 1.5 Riboflavin ( mg) 1.6 Niacin (mg) 17 Vitamin B6 ( mg) 2.2 Folate (µg) 400 Vitamin B12 (µg) 2.2 Calcium (mg) 1,200 Phosphorus ( mg) 1,200 Magnesium ( mg) 320 Iron (mg) 30 Zinc (mg) 15 Iodine (µg) 175 Selenium (µg) 65 asource: Food and Nutrition Board, National Academy of Sciences, National Research Council, 1989.
18 Eating Habits of Pregnant Adolescents
To date, most reports on adolescent pregnancy have emphasized medical outcome variables; information about dietary habits is limited. Dietary habits of nonpregnant adolescents have been explored more fully. Typical eating habits of nonpregnant female adolescents are characterized by meal skipping (95-97), frequent snacking (95, 96, 98-100), frequent consumption of low-nutrient foods
(56, 99, 101, 102), eating away from home (96, 103), and excessive dieting (97,
101, 104).
Some researchers have indicated that adolescents at least attempt to improve their diets during pregnancy (6, 31, 105, 106). However, based on a small number of studies, some of them nearly twenty years old, it would appear that adolescents often practice poor eating habits even during pregnancy. Kaminetzky and co-workers (105) reported that 38% of the 130 adolescents in their investigation consumed less than two servings of milk and dairy products daily.
Other groups of pregnant adolescents also have been found to consume inadequate amounts of dairy products ( 6, 30). Also, consumption of fruits and vegetables, especially those containing good sources of vitamin A and ascorbic acid, is frequently less than recommended (6, 31, 105). In addition, researchers have found that a significant number of adolescents skip meals during pregnancy
(107), snack on "empty calorie foods" (29, 31, 108), and report substituting chips, candy, and sodas for meals (6).
19 Nutritional Status of Pregnant Adolescents
The nutrient composition of diets consumed by pregnant adolescents has been reported by few researchers (29-32, 105-110). If data from each of these studies are combined, and average intakes compared to the 1989 Recommended
Dietary Allowances, one can see that energy, protein, thiamin, riboflavin, niacin, and ascorbic acid intakes generally are adequate. The nutrients most often reported as inadequate include iron, calcium, and vitamin A. Although not reported in all studies, pregnant adolescents' intakes of folate, zinc, magnesium, and vitamin B6 also are frequently less than recommended. The nutrients that are most often consumed in inadequate amounts by pregnant adolescents are the same nutrients that are often reported as inadequate in the diets of nonpregnant adolescents (96, 98, 111-114) and pregnant adults (98, 115, 116). Biochemical indices of nutritional status during pregnancy do not differ in adolescents and adults. Whereas true deficiencies are rare, low serum/blood levels of iron and hemoglobin (29, 30, 117), folate (117, 33), vitamin B6 (118, 119), and zinc (62, 63), are observed more often than any others.
Factors Affecting Food Intake During Pregnancy
Many variables affect dietary intake during pregnancy. Obviously, any factor that affects dietary habits prior to pregnancy also can affect intake during
20 pregnancy. Cultural, ethnic, religious, educational, and social backgrounds lay the
groundwork for eating habits (120) and also can affect beliefs regarding
appropriate maternal nutritional patterns. Other factors including prenatal
education (31, 58, 121-124) and nutritional supplementation (105, 125-127) may
lead to alterations in food-related behaviors during pregnancy. Appetite
compulsions ( dietary cravings and aversions) and beliefs about nutrition during
pregnancy also can affect food intake (34-39). Food preferences may actually
change during pregnancy, and such changes can lead to modifications in typical
dietary habits (34, 37, 122).
In general, there is little available information about the effect these factors
have on the dietary habits of pregnant adolescents; most studies have been done
on pregnant women. In cases where pregnant adolescents were included in the
sample, their data were not separated from those of the adults. Therefore, the
ensuing discussion will combine both groups. Because the emphasis of the current
study was appetite compulsions, beliefs about appetite compulsions, and food
preferences, the bulk of the discussion will focus on these variables.
Educational Level and Nutrition Knowledge
Educational level and the knowledge of appropriate nutrition brought into
a pregnancy have the potential to affect eating behaviors. However, knowledge
does not necessarily translate into action, and unfortunately, a number of researchers have discovered that the nutrition knowledge of pregnant women and
21 adolescents is limited (39, 107, 128). In studies of adolescents, Singleton and associates (107) found that education level was related to dietary behavior; the more educated girls consumed significantly higher quality diets. Other researchers
(31) have failed to find such a relationship.
Prenatal Education
"It is the position of The American Dietetic Association that pregnant adolescents as a group are nutritionally at risk and require nutrition intervention early and throughout the duration of their pregnancies" (3, p. 104 ). One form of intervention is prenatal education. The ultimate goal of nutrition education during pregnancy is to improve dietary behavior; however, education programs offered to both pregnant adults and adolescents have not yielded consistent results. Some researchers report that education during pregnancy improves dietary behavior (31,
58, 121-124), whereas others have found that nutrition education improves knowledge but not necessarily behavior (105, 125-127).
Because of these conflicting results, more research into the appropriate type of education is needed. Orr and Simmons (129) reported that patients often viewed prenatal nutrition advice as restrictive. Negative or noncommittal attitudes toward nutrition professionals were expressed by half of the subjects. Reasons for these attitudes included the perceived difficulty of dietary compliance, the fact that dietitians made them feel guilty about their diets, and the attitude of other health professionals toward nutrition.
22 Nutrition Supplementation
Any program that provides supplemental nutritional foods to prenatal clients has the potential to increase the quality of the diet and in turn to increase weight gain and infant birth weight. The special supplemental food program for women, infants, and children (WIC) administered by the United States
Department of Agriculture provides milk, cheese, iron-fortified cereals, eggs, and fruit juices to high-risk pregnant women and adolescents in an effort to decrease neonatal mortality and raise infant birth weight.
Most evaluations of the WIC program show that the supplemental food program is effective in increasing mean gestational weight gain and mean birth weight in both adolescents and adults (59, 60, 130). However, these studies have not assessed actual dietary intake. Some researchers have found that women and adolescents enrolled in WIC do not always consume the supplemental foods in the quantities recommended (29).
Appetite Compulsions
Some of the dietary changes which happen during pregnancy occur as the result of exogenous factors, such as maternal concern for the health of the fetus and physicians' orders to avoid certain foods. Other changes occur as a result of endogenous factors or factors which originate within the mother. Examples of endogenous factors include such things as changes in the taste of a food and the induction of nausea and vomiting from eating, seeing, or smelling the food (37,
23 38). It is this second type of factors which has the greatest influence on cravings, pica, and aversions, collectively referred to as appetite compulsions (34).
Dietarycravings. A craving may be defined as the compulsive urge to consume a food or substance for which there was no previous excessive desire
(35). Cravings for a wide variety of normal foods have been reported during pregnancy (34-39), and researchers have found that a large percentage of women experience pregnancy-associated dietary cravings. Taggert (39) found that approximately two-thirds of 153 pregnant women surveyed reported cravings.
Tierson (50) interviewed 400 women, 76% of whom reported carvings for at least one food. Schwab and Axelson (34) found that 42 of 60 (70%) pregnant women interviewed reported cravings for specific foods. Stewart and associates (45) interviewed 242 pregnant women in England and Scotland; 55% of the Scots and
69% of the English women experienced cravings.
The most commonly reported craved foods include fruit, fruit juices, milk, dairy products, sweets especially chocolate, and salty foods. Cravings reported less frequently include those for meat, fish, poultry, vegetables, pickles, and cereal products (34-39). British women reportedly experience more cravings for fruit and fruit juices and fewer cravings for sweets and milk than American subjects (39,
45). Based on these observations, it has been suggested that there are cultural and geographic factors which influence the expression of dietary cravings; in some
24 areas, such as in Great Britain, fruits may satisfy the cravings of those women who desire something sweet (131).
The reasons why cravings develop during pregnancy are essentially unexplained, although several theories have been proposed. Some have suggested that the craving may represent a physiological response to maternal or fetal nutritional needs ( 50, 131). This could possibly explain the common cravings for sweets and dairy products. A craving for sweet foods would result in a higher caloric intake which is important for successful pregnancy outcome, and an increase in the consumption of milk and dairy products would provide additional calories, calcium, and protein needed by the pregnant woman. However, this theory does not explain why some pregnant women develop aversions to nutritious foods such as meats and poultry. Also, cravings generally develop early in the course of pregnancy at a time when the additional calories and protein are not considered as important (50).
A second hypothesis is that cravings may be learned behaviors based on cultural factors (50, 132). In other words, a woman craves certain foods because she believes that this is a normal part of pregnancy. A third theory suggests that dietary cravings may be mediated by hormonal alterations or changes in taste and olfactory sensitivity (35, 131). Support for this theory comes from the fact that women often report a craving for a food that is ordinarily disliked. A fourth theory proposes that cravings may be based on the connotative meanings of food,
25 or the ideas and feelings a pregnant woman associates with the food during
pregnancy (34).
Schwab and Axelson (34) asked 60 pregnant women to identify what they
thought caused their own pregnancy-associated dietary cravings. Most of the
women reported that their cravings were due to psychological or symbolic factors
rather than to physiological variables. In other words, the respondents viewed cravings as originating in the mind rather than in the body. Regardless of the
cause, it has been shown that cravings for foods do result in increased consumption of the desired food (50).
Pica. Pica is a form of craving, and can be defined as a pathological
craving for and ingestion of substances not normally considered appropriate for
human consumption (35). Commonly reported craved items include dirt, clay, ice, refrigeratorfr ost, laundry starch, charcoal, soot, baking soda, toilet-bowl air fresheners, mothballs, and coffee grounds ( 40, 41).
Descriptions of pica practices have been reported throughout history ( 133 ).
The ingestion of clay lozenges to treat illness and poisonings reportedly occurred as far back as 10 B.C. However, the incidence of pica in modem times is difficult
to determine. A number of surveys of pregnant women were made in the 50s,
60s, and 70s, most of them in rural areas of the southern United States. In 1950,
Ferguson and Keaton (134) found that 41 % of 331 black women in Mississippi
consumed starch and that another 27% ate clay. Edwards and associates ( 135) in
26 1959 found that almost half of the 86 Alabama women they surveyed admitted consumption of clay and about 27% ate starch; 7% of the patients consumed both.
O'Rourke and colleagues (136) asked 200 randomly selected pregnant women in a Georgia hospital how much clay they had eaten during the course of their pregnancy; 55% reported geophagia, and other women reported consumption of laundry starch, coffee grounds, and paraffin. In an east Tennessee study, Lackey (137) found that 54% of the blacks surveyed and 27% of the whites practiced pica during pregnancy. In a study of 60 pregnant women in Maryland
(34), two black and five white women were the only ones who reported pica.
Each of these women practiced pagophagia (eating ice), and one woman also consumed burnt matches. The majority of the women surveyed, however, had never even heard of the practice of pica.
There is some evidence to suggest that pica also is practiced by pregnant women in areas other than the southern United States. Posner and co-workers
(138) surveyed mostly black women in Harlem, and found that 13% consumed starch during pregnancy, and Snow and Johnson (132) found that over one-third of 40 low-income women studied in Michigan consumed clay, starch, or other non food items. Though most of these studies are dated, it has been suggested that the occurrence of pica among high risk individuals (black women, women from rural backgrounds, and women with family histories of pica) has not changed in the past 20 years (40, 41).
27 In an attempt to explain pica, Lackey (137, 139) has proposed several theories. The first of these theories, the psychological hypothesis, is that pica occurs as a result of a need which has no physiological basis; the need is psychological and occurs in response to pregnancy. Second, the cultural theory suggests that years ago, women ate clay and dirt in order to identify with a lost homeland. The tradition has been passed from generation to generation, and the desire to conform to cultural habits may have sustained the practice.
A sensory craving for pica is the third hypothesis. This theory suggests that the ingestion of certain non-food items satisfies the appetite and relieves hunger pains and nausea. A fourth theory suggests that pregnant women practice pica in order to meet their nutritional needs. However, there is no evidence to support the theory that clay and dirt supply needed nutrients to the deficient mother. A more recent theory is the microbiological one; supposedly, clay produces an intestinal pH which is not favorable for the growth of disease-producing organisms. A final theory proposed to explain the etiology of pica is one associated with physiological changes in taste and smell. Craved substances are usually sweet, sour, or sharp tasting, and supposedly these substances are required to overcome decreased taste sensitivities.
Regardless of the cause, pica is of nutritional concern for several reasons.
It may displace other foods in the diet leading to malnutrition; it may provide excessive calories leading to excessive weight gain; it may be toxic, and finally, the
28 pica substance may actually decrease the intestinal absorption of essential nutrients in the diet (140).
A versions. A dietary aversion is defined as a revulsion for a food or drink that was previously enjoyed (35). Aversions develop suddenly and are very different from avoidances. Avoidances appear to be due to psychological factors whereas aversions tend to be mediated by physiological events such as nausea and vomiting (35).
Aversions have been found to occur not in a limited number of pregnant women but in a sizeable portion of the population. In fact, they occur so commonly that it has been said that aversions may be a normal physiological reaction to the pregnancy. The percentage of women who experience dietary aversions during pregnancy has been reported to be as high as 85% (50). Others have reported smaller figures of 70% and 76% (34, 35). Although the incidence of reported pregnancy-associated dietary aversions is high, two groups of researchers have suggested that aversions occur somewhat less frequently than cravings (34, 39). The significance of this is not known.
Aversions to alcohol, cigarettes, tea, high protein main dishes, especially those containing fish and beef, are most commonly reported during pregnancy (34,
36-39). Tierson and associates (37) found thatat least 10% of the women they surveyed reported aversions to fish, beef, and foods with Italian sauces. This aversion to Italian sauces, particularly those seasoned with oregano, was reported
29 earlier by another researcher (38). Nearly 35% of the women in one study
developed aversions to coffee at some time during pregnancy (3 7), and Hook (38)
reported that 30% of the women he studied decreased consumption of coffee.
This decrease in consumption was reportedly mediated by endogenous factors -
nausea or the loss of taste for coffee. Taggert (39), in a study completed in
Scotland, reported that women developed an aversion to coffee and tea early in
the course of the pregnancy; these subjects proposed that the beverages had a
"peculiar" taste. Taggert also found a large number of women who reported aversions to fried foods or to the smell of foods frying. This also was reported by
Hook (38). In most cases, reported aversions occur earlier than cravings, usually developing between the last monthly period and the twelfth week of gestation
(50). Aversions also reportedly last longer than do dietary cravings.
Women generally give two reasons for decreasing their intake of certain foods during pregnancy: They have a decreased appetite for the food, or the food induces nausea or another negative physiological reaction (34, 37, 39). It has been suggested that the nausea and vomiting of pregnancy is an important physiological reaction because it decreases the ingestion of embryotoxic agents that may be present in the avoided foods (131). If this were true, obviously then aversions would serve to protect the fetus. It is known that alcohol is toxic to the fetus, and a large proportion of women develop aversions to alcohol during pregnancy.
These facts tend to support the theory. Also, if this theory were true, one would expect aversions to occur at a time when the fetus would be most susceptible to
30 toxic agents, during the first trimester of pregnancy. Additional support for this theory comes from the fact that aversions do seem to develop early in the course of a pregnancy.
It has been proposed that women generally decrease their consumption of foods which are aversive to them. With the exception of milk and fruit, Tierson
(50) found this to be true; women consumed less of the foods that induced aversion. In the case of milk and fruits, it is possible that the knowledge that milk and fruit supply important nutrients for both the mother and the fetus overruled the aversion.
Beliefs
Until recently, much of the clinical advise given to pregnant women was based on tradition and supposition. Nutritional care was based on two assumptions, which have since been proven inaccurate. The first theory was that the fetus acts as a parasite; and the second was that mothers have a natural instinct to eat those foods required by the developing fetus (141). While health professionals no longer support these concepts, many women still believe them to be true. In fact, many myths, traditions, and old wives' tales appear to be believed by some contemporary American women (42, 46). The depth of their belief in such ideas and the degree to which diet is affected by such ideas is difficult to determine.
31 Bartholomew and Poston ( 44) interviewed 200 pregnant subjects in South
Carolina; 160 of them were black, and the rest were white. Almost half of the subjects, mostly blacks, believed and practiced one idiosyncrasy associated with food, while only six mentioned more than one that they considered factual. The remaining subjects reported that they had heard of but did not believe in such superstitions. Six women (3%) believed that milk would cause cancer in the mother or the baby and refused to drink it. One of the more commonly held beliefs was that eating pork during the prenatal period would result in death for the mother by rotting the uterus. Even though these subjects eliminated pork from their diets, the dietary change did not interfere with adequate nutrition.
Three percent of the women considered fish to be poisonous to the pregnant woman because it too would rot the uterus. Another three percent believed that eggs were bad for the baby's brain; 6.5% felt that cheese would cause the fetal head to stick to the womb and cause a dry delivery; 10 women (5 % ) felt that green leafy vegetables were taboo because the greens would mark the baby; and
11 subjects felt that diet colas would poison the fetus.
In another study of 40 pregnant women participating in a public health clinic, the women appeared to be aware of what constituted a good diet in the eyes of the health professionals, but over 70% believed that a pregnant women's actions could mark her child, and more than one-third of the subjects related markings to specific foods (132). Other investigators also have reported that a significant number of women believe that a mother's diet can mark the fetus (142-
32 144). However, these studies are somewhat dated. More recently, Kruger and
Maetzold ( 42) interviewed 50 women from a midwestem community about their knowledge of traditional practices in pregnancy. Over 120 myths were recorded and categorized into three classes. The largest group (56 responses) were those practices that might make an impression on the fetus and affect it either positively or negatively. The second group ( 48 responses) were those related to other activities that would insure a healthy baby and safe delivery, and a third group of beliefs were those related to gender determination ( 17 responses).
Some researchers have found that attitudes are related to actual weight gains; women who have negative feelings about gaining weight and those who feel embarrassed, uncomfortable, or self-conscious about their appearance frequently gain less than women who have positive attitudes about prenatal weight gain
(145). Cardenas and associates (128) found that a large percentage of the
Mexican-American women they surveyed felt that they should gain less than 20 pounds so that they would have a smaller baby and thus, an easier delivery.
Palmer et al. (145) reported that 41 % of the 29 women they studied, had negative attitudes about gaining weight, and Stewart and her associates ( 45) found that women in England and Scotland were sometimes uncomfortable with weight gain and resulting appearance; a significant number of these women reported dieting to control increases in weight.
33 Changes in Taste Sensitivity
Many women experience cravings and/or aversions to specific foods during pregnancy, and they frequently report that foods actually taste different than they did prior to pregnancy (34, 37-39). It also has been shown that appetite compulsions can influence dietary intake and therefore, nutritional adequacy ( 50).
Changes in taste and smell may mediate the cravings and aversions seen in pregnancy, although the etiology of these changes is not known. It has been suggested that the sensitivity to salt, sucrose, and bitter compounds may be altered in response to the altered physiology of pregnancy.
Denton ( 49) and Dippel and Elias ( 54) hypothesized that changes in taste which occur during pregnancy are maternal and hormonal in origin. Some researchers have suggested that the development of cravings and aversions in pregnancy are also maternal and hormonal in origin and/or that they are mediated by changes in taste sensitivity (35, 131).
No published reports about the relationship between taste sensitivity and appetite compulsions in pregnant women were found. In fact, very few reports of actual measurements of taste sensitivities in pregnant women were located. The few studies available ( 47-49, 54, 146) do suggest that changes in threshold and preference for the four primary tastes may occur in the pregnant adult, although none of these studies included adolescents in the sample. Research to date has focused more on the evaluation of sweet and salty tastes than on bitter or sour tastes.
34 Sweet taste. Studies comparing the threshold (the level at which a taste is
first detected) for sweet tastes in pregnant and nonpregnant adults have produced
varying results. Some researchers report that the threshold in pregnant women is
higher than for nonpregnant women (49, 146). Others have found that the
threshold for sweet tastes decreases during pregnancy ( 48), while still others
report no difference in the sensitivity for sweet tastes between pregnant and
nonpregnant women ( 47).
Results of preference tests also are contradictory. Brown and Toma ( 47) found no difference in sucrose preferences between pregnant and nonpregnant women, whereas Dippel and Elias (54) suggested that pregnant women prefer weaker solutions of sucrose than either nonpregnant controls or contraceptive users. They also suggested that sucrose preference is not influenced by the trimester of pregnancy. Similar reports in animals were made by Wade and
Zucker (147). They attributed the response to a decreased availability or effectiveness of estrogen in activating the taste mechanism.
Saltytaste. As was true with the data on sweet taste sensitivities, reports of the perception of salty tastes by pregnant women are contradictory. Schmidt, as
reviewed by Denton ( 49) reported that the threshold for salt was 114% higher in pregnant women than in nonpregnant controls. Hansen and Langer ( 146) also reported an increase in the threshold for salt. However, in contrast, Takahashi et al. ( 48) found an increased sensitivity or a decreased threshold to salty tastes.
35 Brown and Toma ( 47) reported that pregnant women were less likely to rank salt solutions in the correct order of concentration than were nonpregnant women.
This also suggests decreased sensitivity.
Animal studies show that pregnant rats have increased salt appetites, and given free access, they consume more salt than nonpregnant controls (148). This suggests that rats may have a decreased sensitivity to or an increased preference for salty tastes during pregnancy. Similarly, Brown and Toma (47) reported that pregnant women preferred saltier solutions than the nonpregnant women and that this pref ere nee was reversed postpartum.
Sour and bitter tastes. Little information regarding pregnant women's taste sensitivities to sour and bitter solutions has been published. However, the available evidence suggests that pregnant women have a decreased sensitivity to these tastes. Schmidt in 1925, as reported by Denton ( 49), found that the taste threshold for acid was 89% higher and for bitter was 60% higher in pregnant vs. nonpregnant women. Hansen and Langer (146) also reported an increase in the threshold for sour and bitter tastes in pregnant women, as did Takahashi et al.
( 48). These results do not lend support to the theory that aversions to foods such as coffee, tea, alcohol, and meat products develop because the pregnant woman is more sensitive to bitter compounds; these studies suggest that she is less sensitive to them.
36 Hormones and taste sensitivity. Relationships between pregnancy
associated cravings and aversions, taste sensitivity, dietary intake, and
estrogen/progesterone levels have been proposed ( 47, 49, 131). Secretion of
estrogen and progesterone increases during pregnancy. The gestational increase
of progesterone occurs earlier than that of estrogen; therefore, the first half of pregnancy is thought to be primarily under the control of progesterone. During
the second half of pregnancy, estrogen secretion increases and serves to neutralize
some of the effects of progesterone (88).
Both hormones have been related to changes in appetite and changes in
taste sensitivity during the human menstrual cycle. In general, caloric intake is
highest during the luteal (postovulatory or premenstrual) phase of the cycle (149,
150). At this time, estrogen levels are low in relation to progesterone levels.
Preferences for sweet tastes also are reported to be higher during the luteal phase
of the menstrual cycle than at times when estrogen levels are higher (150-153).
However, research findings in this area are not consistent; some investigators have
found no relationship between ratings of pleasantness to sweet tastes and the
menstrual cycle (154), or between sucrose intake and the menstrual cycle (149).
Research on laboratory animals suggests an inverse relationship between
estrogen levels and food intake (147, 155-157). Researchers have suggested that
both estrogen and progesterone may play a role in the development of a
preference for sweet tastes, (147, 158-160). Wade and Zucker (147) showed that
preference for sweet solutions was greater among female rats than males;
37 however, the preference difference was not apparent prior to puberty. The age at first estrus and the age at which a sweet preference developed were highly correlated. Their findings substantiated earlier studies by Valenstein et al. (158), who also examined the preference for sweet solutions in adult rats. They found that while both male and female rats preferred a glucose solution over water, the females consumed greater quantities. When the glucose solution was removed, and only water was available, the females decreased their consumption of total fluid. A second experiment by Valenstein et al. (158) compared the fluid intake of male and female rats when the two solution choices were a 3% glucose solution and a much sweeter .25 % saccharin solution. At first, both sexes consumed more of the saccharin solution, but by the third or fourth day, the males switched back to the less sweet solution. Thus, they reached the same conclusion as did Wade and Zucker (147); regardless of age and weight, the average daily intake of sweet solutions is higher in females than males, and the difference is due to hormones.
Preferences for sweet tastes also have been evaluated in laboratory animals during pregnancy. Wade and Zucker (147) reported a sharp decline in the saccharin/water consumption ratio within three days after mating; this alteration continued throughout pregnancy. During the first half of pregnancy, water intake increased while saccharin intake decreased, indicating a true preference shift.
During the latter half of the pregnancy, saccharin intake returned to normal, but water intake rose drastically. Researchers concluded that estrogen was the primary hormone regulating the sweet preference with the progestogens exerting
38 secondary influences. They also suggested that the decreased saccharin preference
before puberty and during pregnancy was a reflection of some process which limits the intake of sweets during times when the organism's requirements for more nutritious and less palatable foodstuffs are greatest.
Dippel and associates (159) showed that the ingestion of synthetic progestogens, in combination with estrogen would result in the suppression of sweet preferences in female rats. They found that the type of progestogen made a difference in the degree of suppression; the more potent synthetic progestogens resulted in a greater suppression than less potent hormones. Because the synthetic progestogens are reported to act by modulating estrogen receptors in the hypothalamus and the pituitary, they result in a retention of estrogen. Thus, these researchers concluded that estrogen resulted in a decreased preference for sweets.
This would suggest that preference for sweet tastes is enhanced when progestogens in relation to estrogens are high, as is seen in pregnancy.
In another study, Zucker (160) observed that the saccharin preference of spayed rats injected with hormones remained high for at least ten days after the treatment was discontinued. His conclusion was that once established, the saccharin preference of female rats becomes autonomous of the hormones originally important for the acquisition of taste preference. In contrast to the previous reports, Kenney and Redick (161) found that neither ovariectomy nor subsequent estrogen replacement had an effect on the female rat's ingestion of saccharin solutions of varying concentrations. They suggested that the
39 modification of glucose ingestion by the ovarian hormones may reflect the influence the hormones have on mechanisms regulating food intake, rather than any separate effect they have on preference.
These studies all suggest that the estrogens, the progestogens, or both influence the preference for sweet tastes, and one can only assume that changes in taste perception occur which mediate the preference changes.
Food Preferences
Pregnant women frequently report that their preferences for certain foods change during pregnancy, and that they either like a food that was previously disliked or they dislike a food that was previously enjoyed. Some of these preference changes could conceivably occur as the result of physiological modifications in the taste mechanism (36, 47-48). However, since the pregnant women themselves admit that some preference changes are due to psychological factors (34, 50), it is obvious that changes in taste sensitivity cannot explain all changes in the food preferences of pregnant women.
Taste and preference are not synonymous. Food preference is a complex reaction, and is affected by a number of psychological and physiological variables
(51-53). Taste is one of the physiological mechanisms that can influence preference. In other words, taste is one part of preference.
40 There is still much to learn about what makes a person eat as she does and much of the available information is controversial. However, some aspects of food acceptance and preference are widely accepted as true: (a) a positive food preference denotes acceptance of a food, while a negative preference implies rejection (53, 162); (b) food preferences are highly individual (53, 162, 163); (c) social status, ethnic traditions, education, family and peer influences, and the importance of health all affect one's preferences (51-53, 162); ( d) food acceptance and preference are learned behaviors ( 51, 52); ( e) some aspects of individual food preferences hold true for a lifetime and others change with time and situations
(53); (f) food habits can be modified or changed (162); (g) a statement of preference assumes that the food is in the appropriate context (53); (h) the three major methods for studying acceptance behavior include attitude tests, sensory evaluations, and consumption measurements (51); and (i) most importantly, taste is only one of the factors that affects preference.
Relationship Between Taste and Preference
There is little objective evidence to suggest that taste sensitivity is correlated with perception, discrimination, or preference at the suprathreshold levels (164-166). One exception to this appears to be a relationship between bitter tastes and food aversions and dislikes. Several studies have demonstrated such a relationship. In 1961, Fischer et al. (167) measured taste thresholds for sucrose, sodium chloride, hydrochloric acid, quinine, and propylthiouracil in 48
41 subjects. They also had each subject complete a checklist regarding dislikes and
aversions to 118 foods. The dislikes for food could not be related to an individual
sensitivity to sucrose, salt, or hydrochloric acid. However, the taste threshold for
bitter substances was related to the percentage of foods disliked. Those
individuals with a low percentage of disliked foods were less sensitive to bitter
tastes while those with a high percentage were very sensitive. These investigators
concluded that while the sources of food preferences and aversions are extremely
complex, evidence indicates that individuals who are sensitive to bitter tastes have a higher number of disliked foods than those who are less sensitive.
Similarly, Glanville and Kaplan (168) assessed taste thresholds for bitter compounds and their relationship to food preferences in 187 adults. They identified significant correlations between a preference for strong tasting · foods and a high taste threshold. They also found a relationship between a sensitivity to bitter tastes and a preference for mild-tasting foods in both males and females. In addition, they found that individuals with the most sensitive abilities to taste bitter
compounds had a higher number of disliked foods.
Jefferson and Erdman (169) also identified a trend toward greater food acceptance by individuals with lower taste sensitivity. However, the trend was not statistically significant. Korsland and Eppright (170) reported greater acceptance of certain foods in children with low taste sensitivity. They also found that the percentage of foods liked and accepted increased as taste sensitivity decreased.
Similar findings were reported by Anliker and co-workers (171).
42 Except for the relationship between bitter taste sensitivity and the number of disliked foods, most researchers have found no relationship between taste acuity and preference. Scherr and King (172), in a study of 125 college students, reported no apparent correlations between suprathreshold intensity ratings and the pleasantness of sweet stimuli. Nilsson and Holm (173) found no relationship between a preference for sweet tastes and threshold measurements in 100 fifteen year old subjects, and Mattes (166) found no relationship between taste sensitivity and perceived intensity of taste in either a water solution or in food. This researcher concluded that these measures provided non-overlapping information about food intake. After studying taste measurements, food preferences, and dietary salt intake in normotensive adults, Pangborn and Pecore (164) reached a similar conclusion. They suggested that discrimination, sensitivity, perceived preference to salt were unrelated and were independent behavioral measures.
Few studies have evaluated the relationship between preference and dietary intake. Shepherd, Farleigh, and Land (174, 175) studied preference for salt in relation to dietary intake of salt. No significant relationship between these variables was identified; however, accurate assessment of human salt consumption is difficult (164). A failure to identifyrelationships between preference and dietary consumption also may be a function of methodology (166); generally, preference has been assessed using artificial media rather than actual foods.
43 Sensory Evaluation
A sensory evaluation is made by the senses of sight, taste, smell, touch, and
hearing when a food is eaten (176). The Sensory Division of the Institute of Food
11 Technology defines sensory evaluation as •••a scientific discipline used to evoke,
measure, analyze, and interpret reactions to those characteristics of foods and materials as they are perceived by the senses of sight, smell, taste, touch, and hearing" (177, p. 40). According to Stone and Sidel (178) this definition emphasizes four major points: (a) it encompasses all of the senses, not just taste perception; (b) it takes into account several different disciplines, but emphasizes the behavioral basis of perception; ( c) it involves the measurement and evaluation of the sensory qualities of food; and ( d) it involves interpretation of such responses.
Sensoryevaluation techniques. Sensory tests can be divided into three types based on the kinds of information they provide. Two of these, the discrimination and the descriptive tests, are analytical tests, while the third is an affective test (176, 178, 179). The affective test includes acceptance and preference evaluations (176, 178). These tests are based on preference measures or measures from which preferences can be determined. The personal feelings of the panelist or subject toward the food being evaluated directs the response (176).
While acceptance tests are used to determine whether or not a product will be
44 used by consumers, preference testing is used to determine whether or not the panelists like the food (179).
Preference can be defined as the expression of appeal of one product over others. It can be measured directly by comparing two or more products with each other and determining wp.ich of the products is most preferred. Preference can be measured indirectly as in determination of whether or not panelists like a food or product being tested (179).
The technique most commonly used for measuring food preferences is the
9-point hedonic scale. Using this scale, the panelists or judges rate each food product from a high score of "like extremely" to a low score of "dislike extremely".
An example of a 9-point hedonic scale is shown in Figure 1.
The 9-point hedonic scale has been used successfully to evaluate a wide variety of products. Advantages to using this type of evaluation system include:
(a) it is simple to describe to panelists; (b) it is equally easy to use; and ( c) it provides reliable and valid results (178). The scale has, however, received criticism from those who believe that untrained panelists do not understand the terms "moderately like" and "moderately dislike" and that they have difficulty discriminating among nine descriptive terms. For these reasons, it is sometimes desirable to modify the 9-point scale to include either five or seven rankings instead of nine. This results in an evaluation system that is easier to use and takes less of the panelists' time. However, the simplification process can result in a loss of detail that may affect the statistical analysis of data (178).
45 SENSORY EVALUATION QUESTIONNAIRE Name ------Date Instructions: Evaluate the product, Sample # 473, for preference. Place a check mark beside the term that best describes your feelings about the food.
Like extremely Like very much Like moderately Like slightly Neither like nor dislike Dislike slightly Dislike moderately Dislike very much Dislike extremely
Comments:
Figure 1. Sample sensory evaluation questionnaire using 9-point hedonic scale.
A second alternative to the 9-point hedonic scale is a modification of the
unstructured scaling technique that is typically used in analytical evaluations. In
this type of analysis, a linear scale is labeled with two descriptors, one at either end of the line. These "anchors" usually describe the two extremes or opposite effects or qualities of the sample (176). The terms "like extremely" and "dislike
extremely" are examples of such anchors. Panelists taste the product being
evaluated and mark the scale at the point corresponding to their preference. This
type of scaling procedure is easy for the panelists to use, although it does require
more individual judgements, and it does take more of the researcher's time to analyze and interpret the results. This type of scale has been used most
46 extensively in descriptive sensory analysis (178), but it may be adapted for use in
preference testing. An example of an unstructured scaling tool is presented in
Figure 2.
Of the three techniques, the 9-point hedonic scale is most commonly used in
preference testing (178).
Tests used to measure taste thresholds are a type of discrimination test and are thus analytical. These tests are performed in order to determine the lowest concentration of a substance that can be detected or the lowest concentration of a substance needed to identify the taste. The procedure for conducting the tests is similar. Varying concentrations of the tastants are dissolved in a medium.
Commonly used tastants include sucrose or saccharin for the measurement of
SENSORY EVALUATION QUESTIONNAIRE Name ------Date ------Instructions: Evaluate the product, Sample # 473 for preference. Indicate how much you like or dislike the product by placing a vertical line on the scale in the appropriate location.
Like extremely Dislike extremely
Comments:
Figure 2. Sample sensory evaluation questionnaire using unstructured scale.
47 sweet taste sensitivities, hydrochloric or citric acids to assess sour, quinine or
caffeine to assess bitter, and sodium chloride to assess salt sensitivities. Subjects
are presented with varying concentrations of the tastant, and the concentration at
which the subject first notices the solution is different from water is the detection
threshold; the concentration at which the subject first identifies the tastant is the
recognition threshold (178).
The intensity ranking test also is used frequently in the assessment of taste
sensitivities. This test is similar to the threshold tests in that varying
concentrations of the tastant are presented. However, in this test, the subjects are
told to rank the solutions either in ascending or descending order of concentration
(176, 178).
The physical environment. The physical environment is an important consideration in sensory analysis. Evaluations should be conducted in special
testing areas where conditions can be controlled and distractions minimized. The area should be well lighted and ventilated, free from foreign odors, quiet, and comfortable. The preparation area should contain sufficient counter space and dry and cold storage areas. Equipment needs vary depending on the tests being conducted, but the preparation room or area should contain everything needed to prepare the samples, clean up after the evaluation process, and store supplies
(176, 178).
48 The preparation area should be separate from the testing area. The panelists should not have to enter the evaluation site through the preparation area, as they might gain information about the products that would affect their evaluations. The sensory analysis procedure requires that panelists make independent judgements about the samples. Thus, in order to eliminate distractions and to prevent communication among panelists, individual evaluation booths are recommended. The booths should be painted a neutral color so as not to influence the appearance of the products being evaluated (176, 178, 179).
As noted earlier, information about food preferences of pregnant adolescents is limited. In addition, the ideal setting for conducting sensory analysis of food preferences represents an atypical eating environment for adolescents.
That is, participation in laboratory food-related research is not congruent with the lifestyles and eating patterns of adolescents. However, the assumption is made that adolescents will respond to the sensory testing procedures and environment in a manner similar to adult participants. The accuracy of this assumption can be tested within the same individuals over time, but it is not known whether pregnant adolescents as a group respond similarly to sensory testing as do postpartum adolescents.
49 Postpartum Adolescents
Detailed descriptions of postpartum adolescents' eating habits and factors that affect postpartum eating habits are not available. Whether the adolescent makes significant dietary changes after delivery of her infant, and the degree to which she is influenced by typical adolescent eating habits ( e.g., meal skipping, frequent snacking, significant consumption of low-nutrient foods, eating meals away from home, and excessive dieting (95-104) are not known. The nutrients most often identified as inadequate in the diets of nonpregnant adolescent females include iron, calcium, folate, vitamin B6, and zinc (96, 98, 111-114). It is not known if these nutrients are consumed in inadequate amounts by postpartum adolescents; the RDA after delivery are lower than during pregnancy. Even so, the RDA are higher for nonpregnant adolescents than for nonpregnant adults.
The RDA for adolescents, divided into two groups based on chronological age, are presented in Table 2.
Summary
Adolescents are considered to be "at risk" during pregnancy. In general, they are more likely than adults to deliver prematurely, and they are also more likely to deliver low-birth weight infants. The observed risks are probably a function of both biological/physiological and environmental factors. Linear growth
50 Table 2. Recommended Dietary Allowances for Female Adolescents.3
Nutrient Age 11-14 Age 15-18
Energy (Kcal) 2,200 2,200 Protein (gm) 46 44 Vitamin A (µg RE) 800 800 Vitamin D (µg) 10 10 Vitamin E (mg a -TE) 8 8 Vitamin K (µg) 45 55 Ascorbic acid (mg) 50 60 Thiamin (mg) 1.1 1.1 Riboflavin (mg) 1.3 1.3 Niacin (mg) 15 15 Vitamin B6 (mg) 1.4 1.5 Palate (µg) 150 180 Vitamin B12 (µg) 2.0 2.0 Calcium ( mg) 1,200 1,200 Phosphorus ( mg) 1,200 1,200 Magnesium (mg) 280 300 Iron (mg) 15 15 Zinc (mg) 12 12 Iodine (µg) 150 150 Selenium (µg) 45 50
8Source: Food and Nutrition Board, National Academy of Sciences, National Research Council, 1989.
51 during adolescent pregnancy probably does not occur in older adolescents;
however, in girls who are chronologically and gynecologically young, some linear
growth may occur during pregnancy. In this group, the nutrient needs of pregnancy may be superimposed upon the nutritional needs for normal growth
and development.
The relationships between prepregnancy weight, gestational weight gain,
and outcome of pregnancy have been well documented by research. The current guidelines for weight gain during pregnancy therefore are based on prepregnancy
weight. Adolescents frequently begin pregnancy at lower weight for height ratios than do adults. Thus, the general consensus is that the typical adolescent should gain more weight during pregnancy than the typical adult.
The RDA for pregnant adolescents do not differ from those for pregnant adults, except for energy. Studies of pregnant adolescents have consistently identified inadequate intakes of iron, calcium, folate, zinc, magnesium, and vitamin
B6• These dietary deficiencies are similar to those observed in both nonpregnant adolescents and pregnant adults.
Many different factors affect dietary intake during pregnancy. Some of these include demographic variables, prenatal education and supplemental food programs, appetite compulsions, beliefs, and changes in taste sensitivity.
Appetite compulsions (cravings, aversions, and pica) occur in a significant number of pregnant women. Common cravings include sweets, dairy products, and fresh fruits and juices. Common aversions include coffee, alcohol, meat, fish,
52 and Italian foods. The etiology of appetite compulsions is not known, although it has been suggested that cravings are psychological in nature, whereas aversions are physiological. It is not known whether adolescents experience cravings and aversions during pregnancy.
Beliefs about nutrition during pregnancy can potentially influence dietary intake. Beliefs of pregnant adolescents, specifically in relation to appetite compulsions, have not been explored previously, although there is some indication that myths, old wives' tales, and superstitions about nutrition during pregnancy are accepted by some women.
Several researchers have reported that taste perception changes during pregnancy. Results of studies in both laboratory animals and in humans have led to the proposition that changes in taste sensitivity may be mediated by changes in femalehormones .
Some women report changes in food preferences during pregnancy. Some of the reported changes may be due to changes in taste sensitivity, but others are likely the result of other factors. Many different factors, both physiological and psychological, influencepreference. Generally, studies of food preferences have been conducted using solutions of specifictastes ( e.g., sweet, sour, salty, bitter).
However, it has been suggested that results obtained using these solutions may not be applicable to real-life situations. Food preferences of pregnant adolescents have not been studied using sensory analysis.
53 Food preferences are generally evaluated using sensory analysis. Several techniques are available to evaluate the degree to which a food is liked or disliked. These include the 9-point hedonic scale, the 7-point hedonic scale, and an unstructured scale. The first two methods provide ordinal data whereas the last results in interval data.
Dietary habits of postpartum adolescents have not been explored sufficiently. It is not known whether adolescents change their diets after delivery.
Factors affecting dietary intake have not been explored in this population.
54 CHAPTER III
METHODOLOGY
Overview
This research was one part of a large investigation of adolescents' eating habits during and after pregnancy. The encompassing objective of the overall study (Agricultural Experiment Station Project AES-TN860) was to identify factors affecting nutritional intake. The factors specific to this portion of the research included (a) reported changes in food consumption patterns and reasons for the changes; (b) incidence of appetite compulsions and related beliefs; and ( c) preferences for specific foods based on sensory analysis. These three factors were studied at two points in time, first during the third trimester of pregnancy, and again at one year postpartum. Funding was provided by the Agricultural
Experiment Station, University of Tennessee Institute of Agriculture.
Human Subjects Approval
Permission to conduct this research study was granted prior to subject recruitment by the Human Subjects Committee at the University of Tennessee,
Knoxville. The research also was approved by the administrative staff in health
55 departments and schools from which subjects were recruited. According to
Tennessee state law, documentation of parental consent for pregnant adolescents was not required.
Selection Criteria and Recruitment
Selection criteria and recruitment procedures were established for the overall study (AES-TN860); two faculty and three graduate students were involved in the process. Selection criteria included white pregnant adolescents between the ages of 11 and 17 at conception, and living within a 120 mile radius of Knoxville,
Tennessee. They were seen for the first time during the third trimester of pregnancy (28 to 35 weeks gestation).
Pregnant adolescents were recruited from health departments, physicians' offices, schools, and residential homes in 40 counties in eastern Tennessee.
Agencies assisting with recruitment were provided publicity posters with detachable postcards and/or referral forms (Appendix A). The forms were completed and mailed to researchers at The University of Tennessee. Upon receipt, a potential participant was sent a letter describing the study, along with an additional letter for her parents or guardian. It was the adolescent's decision as to whether or not she shared the letters with her parents. Copies of the recruitment letters are provided in Appendix B.
56 Approximately four days after the letters were mailed, the potential participant was phoned by one of three graduate students involved in the recruitment process. Again, a brief description of the study was given, and it was emphasized that should she decide to participate, she would be paid $5.00 for each of four completed interviewsand an additional $5.00 for completing food records and questionnaires at home and returning them by mail. If the pregnant adolescent agreed to participate and was already in the third trimester of pregnancy, an appointment was scheduled. If she agreed to participate, but was not yet in the third trimester, she was told which month she could be seen and that she would be contacted again at a later date to set up an interview. If the potential participant could not be reached by phone, a second letter was sent asking her to contact one of the researchers by phone or by mail.
Letters confirming the time and date of the interview and the scheduled location (Appendix C) were mailed immediately after making the appointment.
Phone calls were made the night before the scheduled interview to remind the adolescents of their appointments and to confirm that they would be able to keep them.
Incentives for Participation
In order to encourage adolescents to participate in and complete the overall study (AES-TN860), researchers offered a number of incentives.
57 Participants were seen twice during the third trimester of pregnancy and were paid
$5.00 for each interview. At the end of the first interview, the pregnant
adolescents were allowed to select prizes from a "grab bag". The prizes were gift
wrapped and included such things as baby bibs, rattles, booties, stationery, pens,
and bubble bath. This was seen as an additional incentive to encourage the
adolescents to continue with the study.
Approximately twoweeks after their expected dates of delivery, participants
were contacted by phone by one of the researchers. Information about the birth
was collected, and small baby gifts were mailed.
Three months postpartum, participants were mailed a short survey
(Appendix D). Although the survey was designed to collect information about the
baby ( e.g., sex, birth weight, and length), it's primary purpose was to maintain
contact with AES-TN860 participants.
At approximately six months postpartum, participants were seen by a
fourth graduate student who interviewed them about their babies' health and feeding practices of the adolescent mother. At this time, addresses and demographic data were updated. Participants were paid $5.00 and they received small gifts for their babies at the conclusion of this interview.
At ten months postpartum, participants were sent a letter describing the final phase of the study (Appendix E). Within two to four weeks, they were contacted by phone to set up an appointment. At approximately one year postpartum (11-13 months ± 2 weeks), participants were interviewed again. They
58 were paid $5.00 for the interview and an additional $5.00 for completing food records and questionnaires at home. At the one year postpartum visit, babies were given a toy. The adolescent mothers received a small gift such as a notepad when the final $5.00 payments were mailed.
Instrument Development
All data collection instruments were developed, approved for use, and pilot-tested prior to data collection. The demographic and background information form and the dietary recall/record forms were developed by the team of researchers (two faculty and three graduate students) involved in the larger study at that time. The demographic and background information form was designed in such a way that data could be readily transferred to coding sheets and/or computer. Questions were designed so that socioeconomic status could be calculated easily using the Hollingshead Four Factor Index of Social Status (180).
The dietary recall/record form was similar to those used in previous research studies conducted on adolescents residing in East Tennessee (112, 181).
The instrument was designed to collect not only dietary intake data, but also information about when, where, and with whom each foodwas eaten. Though not necessary for this portion of the study, this information was used by other researchers involved in the larger study.
59 The instrument used to identify changes in dietary consumption patterns was adapted from a variety of standard food frequency checklists. The purpose of this instrument was to compare intake of specific foods before and during pregnancy, and then during and after pregnancy. Therefore, rather than asking for quantitative data, the instructions directed the participant to compare the amount eaten during the two time periods and to indicate whether the amount during pregnancy was more, less, or the same. The instrument also assessed changes in the use of vitamin/mineral supplements, alcoholic beverages, and cigarettes. A second portion of the instrument was designed to obtain information about why dietary changes were made. This portion of the instrument was open ended to allow free responses from the subjects.
The appetite compulsions instrument was designed to assess characteristics of pregnancy-associated cravings and aversions. The instrument was semi structured. As determined by pilot-testing, instructions were specific and terms were defined prior to conducting the interview. Both of the interview instruments described above were pilot-tested twice. The first testing was conducted on 10 pregnant adolescents in a hospital out-patient clinic in Knoxville. Following modifications of the instruments, a second testing was conducted on six pregnant adolescents in a group residential home.
The inventory of beliefs, from which a subgroup of 13 statements about dietary cravings was derived, was adapted by Carruth and Skinner from a similar instrument used to survey dietitians ( 46). It was based on over 2000 statements
60 made by pregnant women and health professionals in Tennessee. A modified Q sort technique was used for item reduction to those beliefs most commonly heard by health professionals. This instrument also was pilot-tested twice, each time on pregnant adolescents in a group residential home in Knoxville.
The instrument used to collect food preference data was designed based on results of pilot-testing in local high school home economics classes. In the first test, students evaluated three different instruments, and then answered questions about the clarity of instructions and ease of use of each instrument. Preference ratings obtained using the three instruments did not differ significantly, and students did not find anyone instrument more difficult to understand than any other instrument. The less structured scale was selected because it would allow more strenuous statistical analysis of data. A second pilot-test was conducted to further evaluate the instrument and its instructions. After each instrument was individually pilot-tested and revised, a pilot-test of the overall AES-TN860interview process was conducted. Interviews were conducted in the mobile laboratory environment. Participants were sixpregnant adolescents living in a group home in Knoxville, Tennessee.
Data Collection
Data were collected in a mobile laboratory by registered dietitians who were graduate students at The University of Tennessee, Knoxville. The mobile
61 laboratory was a rented recreational vehicle (RV), complete with space for all interviews and activities, air conditioning and heat, running water, refrigeration,
and a restroom. The advantage of using the mobile laboratory was that it provided consistent conditions for data collection yet did not require transportation of pregnant adolescents to university laboratories. Meetings were arranged at times and locations convenient to participants. Meeting sites could be participants' homes or schools (if there was adequate parking space) or the parking lots of churches, grocery stores, or other places of business. Data collection for phase I (third trimester of pregnancy) began in April 1989 and continued through December 1989. Data collection for phase II ( one year postpartum) began in July 1990 and continued through March 1991.
Phase One: During Pregnancy
Informed consent and demographic and background data. At the beginning of the first interview, a statement of informed consent (Appendix F) was read and explained by one of the researchers. Participants were given an opportunity to ask questions, and all questions were answered by researchers prior to asking for signed consent. Adolescents were asked to acknowledge their understanding and agreement to participate by signing the statement. Participants also were asked to provide the names, addresses, and phone numbers of at least two people through whom they could be reached ( Appendix G ). The purpose of this was to provide additional means of contact for future interviews.
62 Demographic and background information included participants' ages and
dates of birth; whether or not they were in school and grade level; marital status; living arrangements; if they were married, husband's education and occupation;
and if they were not married, parent's education and occupation. Also collected
were expected delivery dates and attending physicians' names. A copy of the
demographics and background information form is provided in Appendix H.
Dietary data. Dietary data were collected via two 24-hour recalls and two
days' food records. Generally, of the four days, three were weekdays and one was a weekend day. Exceptions occurred when participants failed to follow instructions or when second interviews had to be rescheduled. The first 24-hour recall was taken at the first appointment. Also at the first appointment, instructions, verbal and written, were given for completing the food records. At the second appointment, records were reviewed by the participant and researcher together to ensure completeness and clarity. Following this, a second 24-hour recall was taken. Food models and measuring utensils were used for the recalls, instruction, and review process. The form used to collect dietary data and a copy of the written instructions for completing the forms are provided in Appendix I.
Changes in food consumption patterns and reasons forchange. Changes in consumption/usage of specific foods and selected non-food items and reasons for those changes were assessed during the second interview (third trimester of
63 pregnancy). This information was collected in order to compare the diets of the
same adolescents during pregnancy and prior to conception. Using a modification
of standard food frequency checklists, the pregnant adolescents were able to
qualitatively ( more, less, or the same) compare the amounts of specific foods and
non-food items consumed or used during pregnancy to the amounts consumed or
used prior to pregnancy. A second portion of the questionnaire was open-ended;
adolescents were asked to identify reasons for any reported dietary change. A
copy of the interview instrument is provided in Appendix J. A goal of enrolling
100 subjects was set for this portion of this study.
Appetite compulsions and beliefs about appetite compulsions. Appetite compulsions also were assessed during the second appointment ( third trimester of
pregnancy). A semi-structured interview format (Appendix K) was used to determine the incidence of cravings and aversions, the food and non-food items involved, the stage during pregnancy when each appetite compulsion first occurred, the duration of each, and the reported effect of compulsions on dietary intake. The interview was designed in such a way that the compulsion ( e.g., craving) was defined first, and then two open- and two closed-ended questions about that compulsion followed.
Beliefs about appetite compulsions during pregnancy were assessed at the first appointment. A 38-item instrument was used to measure beliefs about nutrition during pregnancy, and 13 of the items were related to appetite
64 compulsions. These 13 items comprise a subgroup of the inventory of beliefs
(Appendix L). A 5-point Likert-type scale was used to record the level of agreement or disagreement with each belief statement. Possible scores ranged from 0, strongly disagree, to 4, strongly agree.
Food preferences. Preferences for specific foodswere assessed during the second interview using a sensory analysis technique designed to measure degree of like/dislike. Sixteen foods ( eight pairs) were used for the sensory analysis. The foods were purposefully selected because of their varying levels of fat, sugar, and salt. Three pairs differed in fat content (whole milk vs. skim milk; vanilla ice cream vs. vanilla ice milk; and strawberry ice cream vs. strawberry flavored frozen low-fat yogurt), three pairs differedin salt content ( salted vs. unsalted peanuts; salted vs. unsalted potato chips; and saltine crackers vs. low-salt crackers), and two pairs differed in sugar content ( canned sliced peaches packed in heavy syrup vs. canned sliced peaches packed in natural fruitjuices; and chocolate pudding vs. chocolate pudding with added sugar).
Using a randomized incomplete block design procedure customized to meet the purposes of this study, (Appendix M), the first 81 pregnant adolescents enrolled in AES-TN860evaluated eight foods in two segments. The two segments occurred during the same appointment but were separated in time by other research activities performed during the interim. In one segment, participants evaluated four of the six foods which varied in fat content, and in the other
65 session, participants evaluated four of the remaining foods (i.e., those which had
various levels of sugar and salt). This design resulted in 54 pregnant adolescents
evaluating the "fat foods'\ 33 pregnant adolescents evaluating the "sugar" foods,
and 32 pregnant adolescents evaluating each of the "salt foods". A coin toss was
used to determine the order in which the sessions were presented.
The scale used for evaluation was based on preference (i.e., like vs. dislike).
The scale was a horizontal line 10 centimeters in length, marked on one end with
the descriptor "like extremely" and on the other end with the descriptor "dislike extremely". A rating was made by marking the line at a point corresponding with the participant's own idea of preference. Possible scores ranged from Oto 10.00.
Ratings were measured to the nearest 0.5 millimeter. A copy of the rating scale is provided in Appendix N.
Because it was not practical to purchase all foods simultaneously as is usually done in sensory analysis, researchers relied on manufacturers' quality control measures to ensure equality of the food products from one evaluation to the next. Foods were purchased in small quantities as needed, and the same brands were purchased over time. Foods were prepared prior to subjects entering the mobile laboratory. This ensured that participants had no knowledge of the specific foods to be evaluated prior to the evaluation.
Foods were served in individual 3-ounce containers. They were not identified by name or brand; the only identification was a 3-digit code number selected from a table of random numbers. All foods were presented at their
66 appropriate serving temperatures (i.e., chips were at room temperature, ice cream was frozen). Presented along with the foods to be evaluated were water, apple wedges, and carrot sticks. Participants were instructed to eat and drink these prior to tasting each test food in order to eliminate carryover taste from one food to the next.
Phase Two: Postpartum
Data collected at one year postpartum included demographic and background information, dietary data, information about changes in food consumption patterns after pregnancy, appetite compulsions, and food preferences. Essentially, the postpartum interviews were a duplicate of the phase
I (third trimester of pregnancy) interviews with the exception that the instrument used to assess beliefs about appetite compulsions was not administered.
Demographic and background data. Demographic data and background information were updated to account for changes in marital status, living arrangements, education, and socioeconomic status. The only additional information collected was whether or not the adolescent was pregnant again.
Dietary data. Dietary data again included two 24-hour recalls and two days' food records, all collected and reviewed by registered dietitians. Because adolescents were seen only once at 12 months postpartum, the protocol for
67 collection of dietary data differed slightly from that used during the third trimester of pregnancy. As before, the first 24-hour recall was taken during the interview, and instructions for completing food records were discussed. The two days' food records were mailed in, and one of two graduate students contacted the participant in a follow-up phone call to verify their contents and take the final 24- hour recall. This method of using the telephone to collect dietary information has been used previously in studies of adults and children (182, 183). In rare cases
(6.3%) when the participant could not be reached by telephone, dietary data included one recall and three records. The postpartum dietary data included three weekdays and one weekend day, thus replicating the dietary data protocol followed during the third trimester of pregnancy.
Changes in food consumption patterns and reasons for change. The instrument used to assess changes in consumption/usage of specific foods and selected non-food items and the reasons for those changes was the same except the instructions differed; participants were asked to compare the amount of certain foods or groups of foods consumed after pregnancy to the amount consumed during pregnancy. As before, participants also were asked via open ended questions to identify reasons for the changes. All adolescents seen at 12- months postpartum completed this portion of the interview. If a participant was pregnant again at the postpartum visit, she was asked to compare the amount
68 consumed between her two pregnancies to the amount consumed during her first
pregnancy.
Appetite compulsions. Incidence and characteristics of appetite
compulsions after pregnancy were assessed with an instrument modified from the
one used during pregnancy (Appendix 0). The difference in the instrument
reflected the difference in the purpose of data collection. Whereas during
pregnancy, the goal was to identify characteristics of pregnancy-related cravings
and aversions, the goal at postpartum was to determine (a) if pregnancy-related
appetite compulsions still existed; (b) whether new cravings and aversions had
appeared since delivery; and ( c) if cravings were associated with certain periods of the menstrual cycle. The format was again a semi-structured interview, with a
combination of open- and closed-ended questions. Due to time constraints, the inventory of beliefs was not given at the postpartum interview.
Food preferences. Sensory analysis of postpartum food preferences was
conducted as it was in phase I (third trimester of pregnancy). Participants evaluated the same eight foods in the same order as they did during their
pregnancies and used the same rating scale. To maintain consistency in the interview process, participants who were pregnant again at the postpartum interview completed the sensory tests. However, their data were not used in the
69 final analysis because the purpose of this portion of the study was to compare
preferences during and after pregnancy.
Data Analysis
A combination of quantitative and qualitative data analysis procedures were
used. Quantitative data were analyzed using SAS (184) and USSES (185)
procedures. Qualitative data were analyzed using content analysis (186).
Demographic and Background Data
Descriptive statistics were computed for demographic and background information variables. Using the SAS PROC FREQ procedure, frequency distributions were determined for age, marital status, education, living arrangements, and socioeconomic status. Socioeconomic status was determined using the Hollingshead Four Factor Index of Social Status (180). This method of estimating socioeconomic status uses the education and occupations of the primary wage-earners of a nuclear household. In general, when an adolescent lived at home with two employed parents, the education and occupation of each were used; if only one parent worked outside the home, the working parent's education and occupation were used. If the adolescent lived with a spouse or had other living arrangements, the education and occupation of the nuclear unit head of household were used. The Hollingshead method produces possible scores of 8 to
70 66, with 8 being the lowest and 66 the highest score. Hollingshead suggests dividing scores into five groups, which are rough estimates of social status. Scores between 8 and 19 are roughly indicative of lower socioeconomic status, scores of
20 to 29 of lower-middle, scores of 30 to 39 of middle, scores of 40 to 54 of upper-middle, and scores of 55 to 66 of upper socioeconomic status. PROC GLM was used to test for differences in nutrient intake among groups ( categorized according to age, marital status, education, living arrangements, and socioeconomic status). PROC CORR and PROC REG were used to identify relationships between intake of specific nutrients and the Hollingshead Index scores.
Dietary Data
Dietary data were coded and analyzed using the Nutritionist III (5.0 version) Data Analysis package (187). Three graduate students, all registered dietitians, were involved in the process ( only two were involved in the postpartum dietary analysis). One coded the dietary data, another checked the code numbers against the food records/recalls and entered the data into a microcomputer, and the third checked the final printout against the original records/recalls. The students alternated tasks so that each student performed each task approximately one-third of the time. This process was used as a means of ensuring agreement and accuracy. When foods were not included in the analysis package, substitutions were made on the basis of nutrient content. Substitutions were agreed upon by all
71 three graduate students, and a master list of substitutions was maintained along with the original list of foods.
The average intake of nutrients (excluding supplements) across the 4-day period was determined for each participant using the Nutritionist III package.
Group data analysis included minimum and maximum intakes, means, and standard deviations for each of 25 nutrients/food components. Analysis of data was conducted in three ways: (a) using mean nutrient intake in grams, milligrams and micrograms; (b) using the percentage of RDAs (28); and ( c) using nutrients per 1000 kilocalories. Technically, there are no separate RDAs for pregnant adolescents; with the exception of energy, the RDAs for pregnant adolescents are the same as for pregnant adults. The RDA for energy for pregnant adolescents was established by adding 300 Kcal/day for pregnancy to the 2,200 Kcal/day recommendations for normal adolescent females. The nutrients per 1000 Kcal was used to assess nutrient density or dietary quality. Paired t-tests (184) were used to compare dietary intake data during and after pregnancy.
Changes in Food Consumption Patterns and Reasons for Change
Changes in consumption/usage patterns during pregnancy were first analyzed quantitatively. For each of the 27 food groups evaluated, the number of adolescents indicating their consumption increased was determined as were the numbers of adolescents indicating no change and decreased consumption. A list of reasons for each response for each food group was generated. Using content
72 analysis (186) individual responses were merged into categories of similar
responses. Reasons then were categorized as endogenously or exogenously
motivated (34). A similar analysis was conducted on the postpartum dietary
changes and reasons for change.
Appetite Compulsions
Cravings and aversions data were analyzed quantitatively as well as
qualitatively. Frequencies of responses to each closed-ended question (i.e., Have
you experienced cravings?) were determined, and lists of responses to the open
ended questions (i.e., What foods have you craved?) were generated. Content
analysis (186) was used to categorize responses.
The relationship between the number of appetite compulsions and nutrient intake was assessed using the SAS PROC CORR procedure. The SAS analysis of
variance (ANOVA) procedure was used to test for differences in nutrient intake
between adolescents craving and adolescents not craving selected foods.
Beliefs about Appetite Compulsions
Maximum and minimum scores, means and standard deviations, and
median scores for each of the 13 belief statements were determined. Additionally, a total score for each participant was determined by summing the 13 individual scores. As a measure of validity, a Cronbach's alpha rating was determined using the pregnant adolescents' scores. The relationship between total belief scores and
73 the number of appetite compulsions was determined using the SAS correlation procedure.
Food Preferences
Food preference (sensory) data were analyzed using least squares analysis of variance. Mean scores and standard errors were determined for each of the 16 foods using the USSES General Linear Mixed Models (GLMM) procedure least squared means (185). GLMM was used instead of the traditional GLM because the effects being evaluated are neither completely fixed nor completely random;
GLMM assumes that all effects are in fact "mixed effects." Statistical differences in preference scores between each pair of foods were tested with the GLMM
Contrast procedure. Pregnant and postpartum data also were compared using the
GLMM Contrast procedure.
74 CHAPTER IV
RESULTS AND DISCUSSION
Description of Sample
Agencies in 40 counties in eastern Tennessee were contacted for referrals.
Between April 1989 and December 1989, 338 names were received representing
33 of the 40 counties. Of the names received, 97 adolescents (28. 7%) completed the phase 1 ( third trimester of pregnancy) interviews. An additional nine adolescents were interviewed once but did not complete the phase 1 interviews.
The remaining referrals were not interviewed for a variety of reasons, which are summarized in Table 3. Because a large number of potential participants either could not be reached or declined to participate (46.7% ), it is possible that the adolescents enrolled in AES-TN860 were a biased sample and not representative of all white pregnant adolescents in eastern Tennessee. However, no attempt was made to identify characteristics of the nonparticipants.
Approximately two-thirds of the adolescents interviewed during the third trimester of pregnancy also were interviewed at 12 months postpartum. Reasons for lack of follow-up included the researchers' inability to locate the postpartum adolescents, the adolescents' relocation outside the state of Tennessee, and the adolescents' refusal to continue with the study (Table 4). In addition, of the 64
75 Table 3. Disposition of Pregnant Adolescents Contacted to Participate in the AES-TN860 Study.a
Number of Pregnant Adolescents
Referrals received (April 1989 - December 1989) 338
Reasons for not participating:
Could not be contactedb 84
Did not meet criteria for inclusionc 45
Delivered prior to contact 24
Declined to participate 79
Did not complete both interviews during pregnancy 9
Number completing Phase I (during pregnancy) interviews (April 1989 - December 1989) 97 aA study funded by the Agricultural Experiment Station, AES-TN 860: Factors Influencing the Nutritional Health of Adolescents During and Post Pregnancy (1987-1992). bReasons include incomplete mailing addresses; no phone or incorrect number provided; no response to letters. cReferral was not a white pregnant adolescent between the ages of 11 and 17 at conception.
76 Table 4. Follow-up of Pregnant Adolescents at Twelve Months Postpartum.a
Number of Pregnant Adolescents
Total number of adolescents interviewed during pregnancy 97 (Phase I)
Minus those individuals who:
Were without telephones and failed to respond to letters and messages 11
Were unreachable due to incorrect addresses and phone numbers 6
Were living out of state at 12-months postpartum 7
Declined to continue with the study 5
Failed to keep scheduled appointments 4
Total number of adolescents interviewed at 12-months postpartum 64
3Subsample of all pregnant adolescents enrolled in AES-TN860: Factors Influencing the Nutritional Health of Adolescents During and Post Pregnancy (1987-1992).
77 adolescents interviewed postpartum, seven (10.9%) were pregnant again at the
time of the interview, and thus, some data were not appropriate for analysis.
Table 5 shows the number of adolescents completing each component of the study
during the third trimester of pregnancy and at 12 months postpartum. Because
marital status, living arrangements, and socioeconomic status of individual
adolescents frequently changed between the third trimester of pregnancy and 12
months postpartum, and because the postpartum characteristics of the 33
adolescents who did not complete the follow-up were unavailable, it is not possible
to conclude that the 64 subjects seen at postpartum were representative of the 33 who were not seen. However, as described below, the two groups did not appear
to differ when first interviewed during pregnancy.
Demographic and Background Characteristics of Pregnant Adolescents
Table 6 summarizes the demographic and background characteristics of the adolescents seen during pregnancy; results are shown for the entire group of pregnant adolescents (n = 97), for the subset of adolescents completing the sensory analysis (n=81), for the adolescents who were also interviewed after pregnancy
(n=64), and for the adolescents who did not complete the postpartum interview
(n=33). Age at the time of the interviews (during the third trimester) ranged from 14 to 18 years (x = 16.4 ± 1.1 ). Most of the adolescents ( 66%) were enrolled in school and were either attending regular classes or were assigned homebound teachers. Level of education ranged from seven to 12 years
78 Table 5. Number of Adolescents Completing Specific Components of Research Study AES-TN860 During and After Pregnancy. a,b
Component of Study Number of Partici:gants Percent Third Trimester 12 Months Follow-up Pregnancy Postpartum
Demographic data 97 64 66.0
Dietary data (2 recalls and 2 records) 97 57c 58.8
Food frequency questionnaire ( changes in consumption patterns) 97 64 66.0
Cravings/aversions questionnaire 97 64 66.0
Sensory analysis 81d 52 64.2 aAES-TN8 60: Factors Influencing the Nutritional Health of Adolescents During and Post Pregnancy (1987-1992). blncludes adolescents enrolled between April 1989 and December 1989. cData from 7 additional participants were excluded because adolescents were pregnant again at phase II (12-months postpartum) interviews. dSensory analysis was designed foronly 81 subjects.
)
79 Table 6. Demographic and Background Characteristics of Pregnant Adolescents.a
% of Partici�ants Characteristic Group A3 Group Bb Group CC Group Dd (n= 97) (n = 81) (n= 64) (n= 33)
Age (years) 14 6.2 6.2 7.8 3.0 15 14.4 12.3 14.1 15.2 16 30.9 34.6 34.4 24.2 17 33.0 33.3 28.1 42.4 18 15.5 13.6 15.6 15.2
Education (years) 7 3.1 3.7 3.1 3.0 8 6.2 7.4 7.8 3.0 9 22.7 18.5 17.2 33.3 10 27.8 29.6 31.3 21.2 11 21.6 22.2 25.0 15.2 12 18.6 18.5 15.6 24.2
School enrollment yes 66.0 66.7 64.1 66.7 no 34.0 33.3 35.9 33.3
Marital status single 69.1 64.2 65.6 75.8 married 29.9 34.6 34.4 21.2 separated 1.0 1.2 0 3.0
Parity first pregnancy 92.8 91.4 92.2 93.9 second pregnancy 7.2 8.6 7.8 6.1
Living arrangements with one parent 22.7 23.5 23.4 21.2 with both parents 24.7 23.5 25.0 24.2 with spouse 15.5 17.3 17.2 12.1 with parents and spouse 13.4 14.8 15.6 9.1 with other relative 5.2 6.2 4.7 6.1 in group home 13.4 9.9 9.4 21.2 other arrangements 5.2 4.9 4.7 6.1
80 Table 6 (Continued)
% of Partici2ants Characteristic Group Aa Group Bb Group CC Group Dct (n= 97) (n= 81) (n= 64) (n= 33)
Education level of mother <7th grade 4.1 4.9 6.3 0 junior high school 12.4 12.3 17.2 3.0 some high school 30.0 29.7 31.3 27.3 high school graduate 28.9 27.2 34.4 18.2 some college 8.2 8.6 6.3 12.1 college graduate 2.1 1.2 1.6 3.0 unknown 14.4 16.0 3.1 36.4
Education level of father <7th grade 3.1 3.7 4.7 0 junior high school 21.6 23.5 28.1 9.1 some high school 14.4 16.0 10.9 21.2 high school graduate 25.8 24.7 29.7 18.2 some college 9.3 7.4 7.8 12.1 unknown 25.8 24.7 18.8 39.4
Socioeconomic statuse major business, professional 1.0 0 0 3.0 medium business, minor professional, technical 9.3 8.6 9.4 6.1 skilled craftsmen, clerical, sales 17.5 18.6 14.1 27.3 machine operators, semiskilled workers 47.5 48.1 48.4 45.5 unskilled laborers, menial service workers 24.7 24.7 28.1 18.2 aA subset of all pregnant adolescents enrolled in AES-TN860: Factors Influencing the Nutritional Health of Adolescents During and Post Pregnancy (1987-1992). bPregnant adolescents completing sensory analysis ( subset of Group A). 9'regnant adolescents who also completed postpartum interviews ( subset of Group A). dPregnant adolescents who did not complete postpartum interviews ( subset of Group A). esocioeconomic status determined by Hollingshead Four Factor Index of Social Status (1976).
81 (x = 10.1 ± 1.3). Most of the pregnant adolescents (69.1 % ) were not married.
Approximately half (47 .4%) lived with one or both parents, 15.5% with their husbands, 13.4% with husbands and his/her parents, 13.4% in group homes for pregnant adolescents, and 10.4% reported other living arrangements.
Approximately three-fourths of the adolescents were from lower and lower-middle socioeconomic strata. Mean socioeconomic score as determined by the
Hollingshead Four Factor Index of Social Status (180) was 26.2 ± 9.2. While this was the first pregnancy for the majority of the adolescents, 7.2% reported prior pregnancies.
Demographic and Background Characteristics of Postpartum Adolescents
Demographic and background characteristics of the postpartum adolescents are summarized in Table 7; data are reported for the entire group of adolescents seen at 12 months postpartum (n =64); for the subset of adolescents who were not pregnant at 12 months postpartum (n =57); and for the subset of adolescents who completed the sensory analysis at 12 months postpartum (n =52). The three groups do not represent independent samples, and therefore, statistical comparisons are not appropriate. However, subjective evaluation of the data suggests that differences between the groups are minimal.
Ages ranged from 15 to 19 years (x = 17.4 ± 1.1). At 12 months postpartum, approximately one-fourth of the adolescents were enrolled in school. Education level ranged from seven to 13 years (x = 10.8 ± 1.4). At this time, nearly one-half
82 Table 7. Demographic and_ Background Characteristics of Postpartum Adolescents.a
% of Partici:gants Characteristic Group Ab Group Be Group c1 (n= 64) (n= 57) (n =52)
Age (years) 15 6.2 0 7.7 16 10.9 12.3 11.5 17 34.4 31.6 32.7 18 31.3 29.8 28.8 19 17.2 19.3 19.2
Education (years) 7 1.6 1.8 1.9 8 7.8 7.0 7.7 9 6.2 5.3 3.8 10 26.6 26.3 26.9 11 10.9 12.3 11.5 12 43.7 43.9 44.2 13 3.1 3.5 3.8
School enrollment yes 23.4 26.3 25.0 no 76.6 73.7 75.0
Marital status single 48.4 47.4 44.2 married 45.3 45.6 48.1 separated/divorced 6.2 7.0 7.7
Parity one 85.9 94.7 94.2 two 10.9 5.3 5.8 three 3.1 0 0
Living arrangements with one parent 20.3 19.3 19.2 withboth parents 18.8 21.1 21.2 with spouse 37.5 36.8 40.4 withparents and spouse 3.1 3.5 1.9 withother relative 6.2 5.3 3.8 other arrangements 14.1 14.0 13.5
83 Table 7 ( Continued)
% of Participants Characteristic Group Ab Group Be Group c1 (n= 64) (n= 57) (n= 52)
Education level of mother <7th grade 6.3 5.3 5.8 junior high school 17.2 12.3 11.5 some high school 31.3 33.3 32.7 high school graduate 35.9 38.6 38.5 some college 6.3 7.0 7.7 college graduate 1.6 1.8 1.9 unknown 1.6 1.8 1.9
Education level of father <7th grade 4.7 5.3 5.8 junior high school 29.7 28.1 28.8 some high school 10.9 10.5 11.5 high school graduate 31.3 33.3 32.7 some college 7.8 8.8 9.6 unknown 15.6 14.0 11.5
Socioeconomic statuse major business, professional 0 0 0 medium business, minor professional, technical 9.4 10.5 9.6 skilled craftsmen, clerical, sales 14.0 15.8 17.3 machine operators, semiskilled workers 39.1 36.9 36.5 unskilled laborers, menial service workers 37.5 36.9 36.5
aA subset of all postpartum adolescents enrolled in AES-TN860: Factors Influencing the Nutritional Health of Adolescents During and Post Pregnancy (1987-1992). bAil postpartum adolescents interviewed between July 1990 and March 1991. cAdolescents who were not pregnant at 12 months postpartum (subset of Group A). dAdolescents who completed sensory analysis at 12 months postpartum (subset of Group A). esocioeconomic status determined by Hollingshead Four Factor Index of Social Status (1976).
84 of the adolescents were married and 6.2% were separated or divorced. Almost
40% of the postpartum adolescents lived with one or both of their own parents,
37.5% with husbands, 3.1 % with husbands and his/her parents, and 20.3% had other living arrangements. Mean Hollingshead Four Factor Index (180) socioeconomic score at 12 months postpartum was less than during pregnancy
(x = 24.8 ± 9.2), and a greater percentage of adolescents were in lower and lower middle socioeconomic groups. Seven participants were pregnant again at the time of the postpartum interview ( two of these were pregnant for the third time).
Dietary Data
Dietary Intake of Pregnant Adolescents
The average diet ( excluding supplements) of the pregnant adolescents as assessed by two 24-hour recalls and two days' food records (Table 8) provided
2,434 ± 741 calories per day; 50.1 % of the calories were provided by carbohydrate,
14.4% by protein, and 36.6% by fat. This distribution is similar to the caloric distribution of diets consumed by other groups of pregnant adolescents (29-
32, 188).
Current recommendations for the general public are to limit fat intake to
30% of total calories (189,190). Whether this recommendation is appropriate for pregnant women and adolescents is not known. In this study and in previous studies, intake of carbohydrate, especially complex carbohydrate, was less than is
85 Table 8. Mean Dietary Intake and Percent of RDA for 97 Pregnant Adolescents. a,b,c
Nutrient/Food Component Mean ± Std Dev
Kilocalories 2434 ± 741 97 Carbohydrate (gm) 305 ± 97 --e Protein (gm) 88 ± 30 146 Fat (gm) 99 ± 36 --e
Thiamin (mg) 1.8 ± 0.6 123 Riboflavin ( mg) 2.6 ± 1.1 160 Niacin (mg) 21 ± 7 126 Vitamin B6 (mg) 1.7 ± 0.7 75 Folate (µg) 270 ± 144 67 Vitamin B12 (µg) 5.5 ± 3.7 252 Ascorbic acid ( mg) 98 ± 62 140 Vitamin A (IU) 4900 ± 2540 123 Vitamin D (IU) 319 ± 230 80 Vitamin K (µg) 112 ± 122 172 Calcium ( mg) 1291 ± 692 108 Phosphorus ( mg) 1613 ± 644 134 Magnesium ( mg) 255 ± 104 80 Iron (mg) 15 ± 6 48 Zinc (mg) 11 ± 5 72 Iodine (µg) 181 ± 204 103 Selenium (µg) 58 ± 25 78
Sodium (mg) 3512 ± 1201 --e Cholesterol ( mg) 331 ± 149 e --e Sugar (gm) 135 ± 59 -- e Dietary Fiber (gm) 11 ± 5 -- a97 pregnant adolescents are a subsample of all adolescents enrolled in AES-TN860: Factors Influencing the Nutritional Health of Adolescents During and Post Pregnancy (1987-1992). blntake averaged over four days (2 records and 2 recalls). cintake does not include vitamin/mineral supplements. d1989 Recommended Dietary Allowances for pregnancy. eNo RDA for these food components.
86 generally considered desirable. Again, however, no specific recommendations
have been made for pregnant adolescents.
The mean caloric intake was 97% of the recommended dietary allowance
(RDA) for pregnant adolescents. The average daily dietary intake of protein, thiamin, riboflavin, niacin, ascorbic acid, vitamins B12, A, and K, calcium, phosphorus, and iodine exceeded the RDA (Table 8). Mean dietary intake of
several vitamins and minerals were less than the RDA; these included magnesium
(80% RDA), selenium (78% ), vitamin B6 (75% ), zinc (72% ), folate (67% ), and iron ( 48% ). The inadequate consumption of selenium in this sample is probably more a reflection of an incomplete data base (187) than true inadequate intakes.
An intake of iron less than the RDA for pregnancy is typical and to be expected.
According to the Committee on Dietary Allowances (28), pregnant women generally cannot expect to obtain enough iron through diet alone to meet the
RDA; therefore, prenatal iron supplementation is recommended. The low intake of folate is indicative of the low dietary intake of leafyvegetables, legumes, and other foodsources of folate. The same is true for food sources of vitamin B6, magnesium, and zinc.
Results of this study were similar to data reported for other studies of pregnant adolescents (29-32, 106, 108) (Table 9). Energy intake compared to the
1989 RDA was 97% in this group of pregnant adolescents, 100% in another study of pregnant girls in East Tennessee (32), and 113% in a study of low-income pregnant adolescents in California (31). Other researchers have found that energy
87 Table 9. Average Daily Nutrient Intake of Pregnant Adolescents in AES-TN860 compared to Nutrient Intake of Pregnant Adolescents in Other Studies: Percentage of 1989 Recommended Dietary Allowances.a, h,c -- Study No. of Method of %RDA Subjects Assessing Energy Protein Vitamin A Thiamin Niacin Riboflavin Vitamin B6 Folate Ascorbic Iron Calcium Intake Acid
Current study 97 2 records 97 146 123 123 126 160 75 67 140 48 108 2 recalls
Carruth & 34 1 record 100 150 130 107 114 156 - 173 45 105 Skinner, 2 recalls 1991
Endres et 526 1 recall 75 123 121 100 112 138 176 45 66 al., 1987
Endres et al., 1985 pre WIC 91 1 recall 77 128 146 100 114 143 45 61 141 50 79 00 WIC 46 1 recall 76 133 146 107 109 150 50 61 00 123 53 82 Loris et 54 - 1 recall 113 183 204 147 142 242 159 58 139 at., 1985
Osofsky et 88 3 records 71 110 105 67 78 100 113 33 63 al., 1971
King et 17 1 or 2 sets 75 128 99 67 88 112 - - 117 33 67 -al., 1972 of 3 records ·N=97 pregnant adolescents, a subsample of all adolescents enrolled in AES·TN860: Factors Influencing the Nutritional Health of Adolescents During and Post Pregnancy. 1Uietary intake does not include vitamin/mineral supplements. cAll data converted to 1989 Recommended Dietary Allowances. intake averages between 70 and 80% of the RDA, but generally these findings are based on one day rather than four days' of dietary intake (29, 30, 106, 108).
Individual dietary data showed that this group of 97 white pregnant adolescents was not a homogenous group in relation to dietary intake. The mean diet was not necessarily descriptive of the four days' dietary intake of some individuals. Each adolescent had her own set of typical dietary habits. For example, mean caloric intake ranged from 1,174 to 4,717 calories per day.
However, as tested by ANOVA, differences were not related to age, education, school enrollment, marital status, living arrangements, or socioeconomic status. It is possible that the four days of dietary collection were not representative of usual intake for some individuals or that the day-to-day variability in nutrient intake was greater for some adolescents than others. Moreover, it is known that day-to-day variability in dietary intake differs among nutrients (191).
Dietary Intake of Postpartum Adolescents
The average diet at 12 months postpartum (based on two days' food records and two 24 hour recalls) provided 2,004 ± 571 calories per day, or approximately 430 calories less than the average diet during pregnancy. Caloric distribution was 51.5% carbohydrate, 13.3% protein, and 35.2% fat. This distribution was similar to that found during pregnancy and is similar to that identified in groups of nonpregnant adolescents (96, 112, 192).
89 As shown in Table 10, the mean dietary intakes of protein, thiamin, riboflavin,niacin, vitamin B12, and vitamin K exceeded the 1989 RDAs for nonpregnant adolescents. Mean intakes of folate, ascorbic acid, phosphorus, and energy were between 90 and 100% of the RDA. Mean intakes of vitamin B6, vitamin A, vitamin D, calcium, iron, zinc, magnesium, iodine, and selenium were below the RDA. The low intakes of iodine and selenium were probably the result of inadequate data bases (186). The low dietary intakes of vitamin B6, vitamin A, calcium, iron, zinc, and magnesium seen in this group of postpartum girls are similar to patterns seen in nonpregnant adolescents (96, 98, 111-114 ), and these results can be expected when daily consumption of vegetables, fruits, legumes, whole grain breads and cereals, and milk and dairy products is low.
Comparison of Diets During and After Pregnancy
When average daily nutrient intakes during the third trimester of pregnancy and at 12 months postpartum were compared, significant differences were identified for all nutrients. In each case, consumption was higher during the third trimester of pregnancythan at 12 months postpartum. No significant differences in nutrient density ( nutrient per 1000 Kcal) forthe macronutrients were found; also, no differences were identified for niacin, vitamins B6, B12, and K, iron, zinc, and selenium (Table 11). Based on nutrient density per 1000 calories, significant differences were found for thiamin, riboflavin, folate, ascorbic acid, vitamins A and
90 fo Table 10. Mean Dietaryb Intake and Percent of RDA r 57 Postpartum Adolescents.a ,
e Nutrient/Food Component Mean ± Std Dev % RDAd,
Kilocalories 2004 ± 570 91 --f Carbohydrate (gm) 259.3 ± 83.0 d e Protein (gm) 67 ± 22 152 ,145 f Fat (gm) 79 ± 26 --
Thiamin ( mg) 1.3 ± 0.5 120 Riboflavin (mg) 1.6 ± 0.8 126 Niacin (mg) 19 ± 8 127 d ge Vitamin B6 ( mg) 1.3 ± 0.7 84 ' 7 Folate (µg) 177 ± 106 98 Vitamin B12 (µg) 3.8 ± 1.9 189 Ascorbic acid ( mg) 58 ± 38 97 Vitamin A (IU) 3028 ± 2091 76
Vitamin D (IU) 159 ± 131 40 d e Vitamin K (µg) 70 ± 84 126 ' 116 Calcium (mg) 772 ± 341 64
Phosphorus ( mg) 1148 378 96d e Magnesium (mg) 171 ± 65 57 ' 61 Iron (mg) 12 ± 5 79 Zinc (mg) 9 ± 5 78
Iodine (µg) 68 ± 77 46 e Selenium (µg) 40 ± 22 god ' 73 f Sodium (mg) 2715 ± 859 -- Cholesterol ( mg) 257 ± 120 --f 111 ± 58 --f Sugar (gm) f Dietary Fiber (gm) 8 ± 4 -- a57 postpartum adolescents are subsample of all adolescents enrolled in AES-TN860: Factors Influencing the Nutritional Health of Adolescents bDuring and Post Pregnancy (1987-1992). Mean intake is based on four day average (2 records and 2 recalls). clntake does not include vitamin/mineral supplements. d1989 RDA for 46 adolescents aged 15 to 18 years. e19g9 RDA for 11 adolescents aged 19 years. rNo RDA for these food components.
91 Table 11. Comparison of Adolescents' Dietary Intake During the Third Trimester of Pregnancy and at Twelve Months Postpartum.a,b,c
Pregnant - Post12artum Difference Nutrient Mean Difference Mean Difference ( ± Std Error) Per 1000 Kcal ( ± Std Error)
Calories 569 ± 95 * Carbohydrate (gm) 68 ± 12 * -1 ± 3 Protein (gm) 24 ± 5 * 2 ± 1 Fat (gm) 26 ± 5 * 1 ± 1
Thiamin (mg) 0.6 ± 0.1 * 0.1 ± 0.0 * Riboflavin (mg) 1.0 ± 0. 1 * 0.3 ± 0.1 * Niacin (mg) 3 ± 1 * 1 ± 0 Vitamin B6 (mg) 0.5 ± 0.1 * 0.1 ± 0.0 Folate (µg) 117 ± 22 * 28 ± 9 * Vitamin B12 (µg) 2.1 ± 0.6 * 0.4 ± 0.3 Ascorbic acid ( mg) 50 ± 9 * 14 ± 4 * Vitamin A (IU) 2034 ± 427 * 563 ± 202 * Vitamin D (IU) 174 ± 27 * 52 ± 10 * Vitamin K (µg) 42 ± 20 * 10 ± 9 Calcium ( mg) 560 ± 86 * 128 ± 30 * Phosphorus ( mg) 533 ± 82 * 79 ± 24 * Iron (mg) 3.1 ± 1.0 * 0.0 ± 0.4 Magnesium (mg) 103 ± 14 * 19 ± 5 * Zinc (mg) 2 ± 1 * 0 ± 0 Iodine (µg) 109 ± 26 * 30 ± 8 * Selenium (µg) 19 ± 4 * 3 ± 2 Cholesterol ( mg) 94 ± 23 * 5 ± 10 Dietary fiber (gm) 4 ± 1 * 1 ± 0 * Sugar (gm) 37 ± 10 * 1 ± 4 Sodium (mg) 828 ± 162 * 24 ± 50
3N = 57 adolescents who comprise a subsample of all adolescents enrolled in AES-TN860: Factors Influencing the Nutritional Health of Adolescents During and Post Pregnancy (1987-1992). bintake averaged over four days (2 records and 2 recalls). cintake does not include vitamin/mineral supplements.
92 D, calcium, phosphorus, magnesium, and iodine. Additional analyses of dietary data are provided in Appendix P.
Dietary Changes
In an ideal research situation, dietary changes during pregnancy would be assessed by conducting a longitudinal study of the same group of adolescents before, during, and after pregnancy. However, longitudinal studies are not without bias and retention problems. In addition, the cost and practicality preclude them in studying adolescents, except in small numbers, which in turn presents a problem in generalizing results to the larger population. One way to conduct an indirect analysis would be to compare the average diet of pregnant adolescents to the average diet consumed by a demographically similar group of never-pregnant adolescents. A second way to assess dietary change would be to ask pregnant adolescents to identify perceived changes in consumption patterns during pregnancy. This latter technique was used in the current study.
Reported Changes in Food Consumption During Pregnancy
Based on interviews using the modified food frequency checklist (Appendix J), most of the pregnant adolescents reported that their typical diets changed during pregnancy. Table 12 shows the percentage of pregnant adolescents reporting increases, decreases, and no change in their prepregnancy diets. Almost two-
93 Table 12. Adolescents' Self-reported Changes in Usage Patterns for Selected Food and Non-food Items During vs. Prior to Pregnancy.a,b
Category of Food/ Pre:gregnan�vs. Pregnan� Change Non-food Items Less Same More
<------% Participants ------>
Total amount of food 11.3 24.7 63.9 Milk 9.3 18.6 72.2 Cheese, ice cream and other dairy products 6.2 34.0 59.8 Meats 27.8 39.2 33.0 Dried beans and peas 27.8 53.6 18.6 Vegetables 11.3 37.1 51.5 Fresh fruit and unsweetened fruit juices 6.2 25.8 68.0 Sweetened fruitsand juices 27.8 41.2 30.9 Breads and cereals 9.3 33.0 57.7 Sauces and gravies 32.0 41.2 26.8 Fats and oils 33.0 47.4 19.6 Spicy foods 36.1 27.8 36.1 Chips, nuts, and snack crackers 28.7 35.1 41.2 Coffee 22.7 71.lc 6.2 Tea 25.8 52.6d 21.6 Soft drinks 28.9 36.1 35.1 Koolade 20.6 53.6 25.8 Sweets, except chocolate 26.8 44.3 28.9 Chocolate 23.7 25.8 50.5 Fast foods (e.g. McDonalds) 35.1 27.8 37.1 Vitamin pills 5.2 9.3 85.6 e Alcohol 25.8 74.z 0 Cigarettes 26.8 69.lf 4.1
3N = 97 pregnant adolescents who comprise a subsample of all adolescents enrolled in AES-TN860: Factors Influencing the Nutritional Health of Adolescents During and Post Pregnancy (1987-1992). bData were collected with semi-structured interviews using a modified food frequency questionnaire (Appendix J). c51.s% did not consume coffee prior to pregnancy. d14.4% did not consume tea prior to pregnancy. e72.2% did not consume alcohol prior to pregnancy. f55.7% did not smoke prior to pregnancy.
94 thirds of the adolescents reported increases in the total amount of food consumed; over half reported increased consumption of milk and dairy products, fresh fruits and fruit juices, vegetables, and breads and cereals. These changes would suggest increased intakes of calories, calcium, phosphorus, riboflavin, ascorbic acid, vitamin D, vitamin � and the B-complex vitamins. The percentages of pregnant adolescents reporting increased consumption of milk and vegetables were higher in this study than in others (6, 31). However, just because consumption of certain foods increased, this does not necessarily indicate that intakes met recommendations. In this study, the mean serving of dairy products/day was 3.15
+ 2.09. This is within the range recommended in the Dietary Guidelines for
Americans (189), but lower than amounts recommended in the Basic Four (193).
Milk consumption by this group of pregnant adolescents was higher than that reported by Endres and co-workers (29), and by Schneck and associates (6), but lower than that reported by Loris et al. (31 ). The mean number of servings of meats/proteins was within the recommended range (189, 193), as was the mean number of servings of fruits and vegetables.
A large percentage of pregnant adolescents also reported decreased consumption of certain "high fat" or "low nutrient" foods. Approximately one-third reported decreased consumption of sauces and gravies, fats and oils, and fast foods. At least 20% also reported decreased consumption of caffeine-containing beverages, chips, nuts, and snack crackers, and sweets. However, a similar number of adolescents reported increased consumption of these foods. Schneck
95 and co-workers (6) reported that 37% of 99 low-income pregnant adolescents surveyed consumed at least three servings per day of "low nutrient dense" foods, while another 13% consumed four or more servings.
Most pregnant adolescents in this study (85.6%) reported taking more vitamin/mineral supplements during than prior to pregnancy. Other researchers also have reported increased use of supplements during pregnancy, although what generally is assessed is whether or not supplements have been prescribed (31,
194). In this case, it is noteworthy that several of the adolescents admitted that they did not follow their physicians' directions in taking the supplements; some indicated that they took the pills for a short time and then ceased use, while others reported sporatic consumption. Thus, reliance on prescribed vitamin supplementation to meet the nutritional needs of pregnant adolescents is not warranted.
Consumption of alcohol and usage of tobacco were reportedly low prior to pregnancy. Even so, in most cases, use of these products decreased during pregnancy.
Reported Reasons for DietaryChange During Pregnancy
This group of pregnant adolescents identified many reasons for changing their diets during pregnancy. The reasons included endogenous (physiological) factors as well as exogenous variables. Endogenous factors included such things as changes in appetite or thirst (increased or decreased), dietary cravings, and
96 changes in taste. Nausea, morning sickness, and heartburn also were mentioned,
as were prevention of these same physiological disturbances.
Exogenous factors included concern for personal and/or fetal health, the influences of family and/or health professionals, and changes in availability of specific foods. Several of the adolescents indicated that their living arrangements had changed since becoming pregnant and that the types of foods prepared and served at their new residences were different from those served at their previous homes.
Table 13 shows the endogenous and exogenous reasons for increasing consumption/usage of specific foods and selected non-food items during pregnancy. Generally, a combination of factors were cited for each category.
Nearly half of the pregnant adolescents reported dietary changes due to increased appetite. The other physiological reasons cited most often as motivators of dietary change included "cravings" and "changes in taste". There is significant evidence that women experience dietary cravings during pregnancy (34, 35, 37, 38, 131) and some indirect evidence that the taste of certain foods also might change during pregnancy ( 47-49, 54). These data support those findings.
Nearly three-quarters of the pregnant adolescents reported increased consumption of milk during pregnancy. Reasons for these changes provide some evidence that certain nutrition education messages about diet during pregnancy are being internalized and acted upon by adolescents. The primary reasons cited for increasing consumption were "concern for the baby", "health professionals'
97 Table 13. Adolescents' Endogenous and Exogenous Reasons for Increasing Consumption of Specific Foods and Usage of Selected Non-food Items During Pregnancy.a, b,c
TOTAL AMOUNT OF FOOD number of subjects (n)=62; number of responses (nr)=86
Endogenous reasons Exogenous reasons -increased appetite ( 47) -concern forbaby ( 15) -prevents nausea (2) -family's influence (8) -cravings (1) -personal health (7) -health professionals' influences (3) -boredom/nerves (3)
MILK n=70, nr=97
Endogenous reasons Exogenous reasons -tastes better (9) -concern forbaby (29) -cravings (7) -health professionals' influences (20) -thirstier (4) -personal health (16) -prevents heartburn (3) -family's influence (8) -increased availability (1)
CHEESE, ICE CREAM, AND OTHER DAIRY PRODUCTS n=58, nr=79
Endogenous reasons Exogenous reasons Unsure -cravings ( 17) -concern forbaby (10) (2) -tastes better (14) -personal health (9) -increased appetite (1) -health professionals' influences (9) -increased availability (6) -family's influence( 4) -substitute for milk (4) -snacking more (2) -does not make me sick (1)
MEATS n=32, nr=36
Endogenous reasons Exogenous reasons Unsure -craving (9) -increased availability (5) (3) -increased appetite (7) -concern for baby (3) -tastes better (5) -family's influence (2) -health professionals' influences (2)
98 Table 13 (Continued)
DRIED BEANS, PEAS, AND LEGUMES n=18, nr=23
Endogenous reasons Exogenous reasons Unsure -craving ( 6) -increased availability (4) (2) -tastes better (3) -personal health (2) -hungrier (2) -substitute for meats (2) -concernfor baby (1) -family's influence (1)
VEGETABLES n=50, nr=60
Endogenous reasons Exogenous reasons Unsure -tastes better (8) -concern for baby (12) (3) -cravings (7) -family's influence (8) -hungrier (3) -personal health (7) -increased availability (6) -health professionals' influences ( 4) -substitute for meats (2)
FRESH FRUITS AND UNSWEETENED FRUIT JUICES n=66, nr=91
Endogenous reasons Exogenous reasons Unsure -craving (17) -personal health (15) (5) -tastes better (11) -concern forbaby (10) -thirstier ( 5) -increased availability (9) -hungrier (2) -health professionals' influences (6) -family's influence (4) -non-fatteningsnacks (2) -quick and easy (2) -substitute forsodas (2) -substitute forvegetables (1)
SWEETENED FRUITS AND JUICES n=30, nr=40
Endogenous reasons Exogenous reasons Unsure -tastes better (11) -increased availability (6) (1) -craving (9) -concern for baby (4) -thirstier (3) -personal health (3) -health professionals' influences (1) -substitute forsodas (1) -non-fatteningsnacks (1)
99 Table 13 (Continued)
BREADS AND CEREALS n=56, nr=68
Endogenous reasons Exogenous reasons Unsure -hungrier (15) -personal health (8) (3) -tastes better (5) -concern for baby (6) -cravings (5) -increased availability (6) -filling (3) -eat breakfast now (4) -does not make me sick (3) -family's influence (3) -neutralize morning -snacking on these foods more (3) sickness (2) -health professionals' influences (2)
SAUCES AND ORAVIES n=26, nr=29
Endogenous reasons Exogenous reasons Unsure -tastes better (7) -family's influence (2) (2) -need saltiness/flavor (6) -increased availability (2) -cravings ( 6) -concern for baby (1) -hungrier (3)
FATS AND OILS n=19, nr=21
Endogenous reasons Exogenous reasons Unsure -hungrier (4) -appeals to me now (3) (5) -need salty flavor (3) -concern forbaby (2) -craving (2) -I know I shouldn't -filling ( 1) eat them (1)
SPICY FOODS n=35, nr=42
Endogenous reasons Exogenous reasons Unsure -craving (18) -appeals to me now (3) (3) -need extra seasoning (8) -increased availability (2) -tastes better (6) -hungrier (2)
CHIPS, NUTS, AND SNACK CRACKERS n=40, nr=67
Endogenous reasons Exogenous reasons Unsure -hungrier (21) -quick and easy (18) (3) -cravings ( 6) -increased availability (5) -tastes better (3) -appeals to me more (3) -need salty flavor (3) -health professionals' -prevent morning sickness (3) influences (2)
100 Table 13 (Continued)
COFFEE n=6, nr=6
Endogenous reasons Exogenous reasons -craving (2) no responses given -tastes better (1) -thirstier (1) -keeps me awake (1) -prevents headache (1)
TEA n=21, nr=23
Endogenous reasons Exogenous reasons -thirstier (7) -increased availability (3) -want sugar (3) -substitute for sodas (3) -tastes better (2) -I'm not supposed to have -cravings (2) it (1) -keeps me awake ( 1) -cools me down (1)
SOFrDRI NKS n=34, nr=36
Endogenous reasons Exogenous reasons -thirstier (16) -increased availability ( 4) -addicted to caffeine (6) -nutritional reasons (1) -cools me down (3) -tastes better (2) -want sweetness (2)
KOOLADE n=25, nr=32
Endogenous reasons Exogenous reasons -tastes better (6) -substitute for sodas (11) -thirstier ( 4) -personal health ( 4) -craving ( 4) -increased availability (3)
SWEETS,EXCEPT CHOCOLATE n=28, nr=29
Endogenous reasons Exogenous reasons Unsure -craving (16) -increased availability (4) (4) -tastes better (5)
101 Table 13 (Continued)
CHOCOLATE n=49, nr=49
Endogenous reasons Exogenous reasons Unsure -craving (33) -increased availability (5) (3) -need sugar ( 4) -tastes better ( 4)
FAST FOODS n=19, nr=39
Endogenous reasons Exogenous reasons Unsure -craving (14) -increased availability (11) (3) -tastes better (3) -don't want to cook ( 6) -hungrier (2)
VITAMIN PILLS n=83, nr-101
Endogenous reasons Exogenous reasons -craving ( 1) -health professionals' influences (76) -concern for baby (13) -personal health (8) -family's influence (3)
ALCOHOL n=O, nr=O
CIGARETTES n=4, nr=5
Endogenous reasons Exogenous reasons -craving ( 1) -nervous habit (3) -increased availability (1) aN =97 pregnant adolescents who comprise a subsample of all adolescents enrolled in AES-TN860: Factors Influencing the Nutritional Health of Adolescents During and Post Pregnancy (1987-1992). bData collected using semi-structured interview format (Modified food frequencychecklist - Appendix J). Data analyzed using content analysis. cEndogenous = physiological reasons. Exogenous = all other reasons.
102 influences", and "personal health". These same reasons were frequently cited as
factors motivating increased consumption of other dairy products, vegetables, fresh
fruits and juices, breads and cereals, and vitamin supplements. When adolescents
reportedly increased consumption of meats, sauces and gravies, fats and oils, spicy foods, coffee, tea, soft drinks, and sweets, endogenous factors such as "taste changes" and "cravings" were most likely to be the cause.
The endogenous and exogenous reasons given by adolescents for decreasing consumption/usage of specific foods and selected non-food items during pregnancy are outlined in Table 14. Endogenous factors were cited more often than exogenous factors as reasons for decreasing consumption of milk and other dairy products; meats; dried beans, peas, and legumes; breads and cereals; sauces and gravies; spicy foods; and vitamin pills. Exogenous factors were reported more often than endogenous factors as reasons for decreasing consumption/usage of fats and oils; chips, nuts, and snack crackers; tea and soft drinks; fast foods; alcohol; and cigarettes. "Concern for the baby", "concern for personal health", and "health professionals' influences" frequently were cited as reasons for decreasing consumption/usage of coffee, tea, soft drinks, chips, alcohol, and cigarettes.
It is interesting that although "health professionals' influences" was mentioned
164 times as a reason for dietary change (increases and decreases), the health professional was identified as a nutritionist only four times. The health professional most frequently cited as having an influence on dietary intake was the physician. However, contact with dietitians during pregnancy was not assessed. It
103 Table 14. Adolescents' Endogenous and Exogenous Reasons forDecreasing Consumption of Specific Foods and Usage of Selected Non-food Items During Pregnancy.a,b,c
TOTAL AMOUNT OF FOOD number of subjects (n)=ll; number of responses (nr)=13
Endogenous reasons Exogenous reasons -nausea (6) -family's influences (1) -decreased appetite (3) -increased sensation of fullness (3)
MILK n=9, nr=12
Endogenous reasons Exogenous reasons Unsure -tastes different (7) -no responses given (1) -nausea (4)
CHEESE, ICE CREAM, AND OTHER DAIRY PRODUCTS n=6, nr=6
Endogenous reasons Exogenous reasons -tastes different ( 4) -prevents excess -makes me sick (1) weight gain (1)
MEATS n=27, nr=29
Endogenous reasons Exogenous reasons Unsure -tastes different (12) -doesn't appeal to me (3) (1) -makes me sick (11) -too heavy/filling (1) -prefervegetables (1) -prevents excess weight gain (1)
DRIED BEANS, PEAS, AND LEGUMES n=27, nr=31
Endogenous reasons Exogenous reasons -tastes different (14) -doesn't appeal to me (3) -makes me sick (10) -no time to prepare (2) -parents don't make me eat these foods (2)
104 Table 14 (Continued)
VEGETABLES n=ll, nr= ll
Endogenous reasons Exogenous reasons Unsure -tastes different (5) -doesn,t appeal to me (4) (1) -make me sick (1) -no time to prepare (1) -less available (1)
FRESH FRUITS AND UNSWEETENED FRUIT JUICES n=6, nr=6
Endogenous reasons Exogenous reasons Unsure -tastes different (3) -less available (2) (1) -prevents excess weight gain (1)
SWEETENED FRUITS AND JUICES n=27, nr=32
Endogenous reasons Exogenous reasons Unsure -tastes different (12) -less available ( 4) (4) -makes me sick (3) -prevents excess weight gain (3) -personal health (3) -health professionals' influences (3)
BREADS AND CEREALS n=9, nr=lO
Endogenous reasons Exogenous reasons Unsure -tastes different (5) -doesn't appeal to me (2) (1) -makes me sick (1) -less available (2)
SAUCES AND ORAVIES n=31, nr=37
Endogenous reasons Exogenous reasons Unsure -makes me sick (13) -less available (7) (2) -tastes different (8) -doesn,t appeal to me (3) -family'sinfluence (2) -prevents excess weight gain (2)
105 Table 14 (Continued)
FATS AND OILS n=32, nr=41
Endogenous reasons Exogenous reasons Unsure -makes me sick (11) -prevents excess weight gain (9) (1) -tastes different (3) -less available (5) -less appetite (1) -family's influence (3) -health professionals' influences (3) -personal health (3) -concern forbab y (1) -doesn't appeal to me (1)
SPICY FOODS n=35, nr=38
Endogenous reasons Exogenous reasons -makes me sick (29) -health professionals' -tastes different (3) influences (3) -dislike smell (2) -concern forbaby ( 1)
CHIPS, NUTS, AND SNACK CRACKERS n=28, nr=30
Endogenous reasons Exogenous reasons Unsure -tastes different (6) -personal .health (6) (2) -makes me sick (3) -prevents excess weight gain (4) -less available (2) -health professionals' influences (2) -family'sinfluence (2) -doesn't appeal to me (2) -concern for baby
COFFEE n=22, nr=28
Endogenous reasons Exogenous reasons Unsure -tastes different (10) -personal health (5) (1) -makes me sick (3) -concern forbaby (4) -health professionals' influences (3) -family's influence (1) -doesn't appeal to me (1)
106 Table 14 (Continued)
TEA n=28, nr=28
Endogenous reasons Exogenous reasons Unsure -tastes different (5) -personal health (10) (1) -makes me sick ( 1) -concern for baby (6) -health professionals' influences ( 4) -less available (1)
SOFfDRINKS n=28, nr=33
Endogenous reasons Exogenous reasons -tastes different (3) -personal health (10) -makes me sick (2) -health professionals' influences (9) -family's influence ( 4) -concern for baby (3) -prevents excess weight gain (1)
KOOLADE n=20, nr=23
Endogenous reasons Exogenous reasons -tastes different (8) -less available (3) -makes me sick ( 4) -prevents excess weight gain (3) -juices more available (2) -tired of it (1) -does not satisfythirst (1)
SWEETS, EXCEPT CHOCOLATE n=26, nr=26
Endogenous reasons Exogenous reasons -tastes different (5) -personal health (4) -makes me sick (5) -prevents excess weight gain (3) -less available (2) -substitute more nutritious foods (2) -doesn't appeal to me (2) -concern for baby (1) -familfs influence (1) -health professionals' influences (1)
107 Table 14 (Continued)
CHOCOLATE n=23, nr=25
Endogenous reasons Exogenous reasons -makes me sick (9) -concern forbaby (3) -tastes different (3) -personal health (3) -prevents excess weight gain (2) -less available (2) -family's influence(1) -health professionals' influences (1) -doesn't appeal to me (1)
FAST FOODS n=34, nr=38
Endogenous reasons Exogenous reasons Unsure -makes me sick (8) -less available (16) (2) -tastes different (6) -don't like going out (2) -personal health (2) -family's influence (1) -tired of it (1)
VITAMIN PILLS n=5, nr-5
Endogenous reasons Exogenous reasons -makes me sick (5) -concern for baby ( 1) -forgetfulness (1)
ALCOHOL n=25, nr=34
Endogenous reasons Exogenous reasons -tastes different (4) -concern forbaby (17) -makes me sick (3) -personal health (4) -health professionals' influences (3) -family's influence (2) -doesn't appeal to me (1)
108 Table 14 (Continued)
CIGARE1TES n=26, nr=35
Endogenous reasons Exogenous reasons -makes me sick (9) -concern for baby (16) -tastes different (1) -personal health (6) -family's influence (1) -health professionals' influences (1) -doesn't appeal to me (1) aN =97 pregnant adolescents who comprise a subsample of all adolescents enrolled in AES-TN860: Factors Influencing the Nutritional Health of Adolescents During and Post Pregnancy (1987- 1992). bData collected using semi-structured interview format (modified food frequency checklist - Appendix J). Data analyzed using content analysis. cEndogenous = physiological reasons; Exogenous = all other reasons.
109 is possible that such contact was limited, although adolescents attending public health clinics and enrolled in WIC should have received prenatal diet counseling along with supplemental foods.
While most of the pregnant adolescents in this study would qualifyfor WIC, enrollment was not assessed. However, a number of the pregnant adolescents indicated that due to the supplemental food program, access to certain types of foods increased during pregnancy.
Reported Changes in Food Consumption After Pregnancy
The dietary changes reported during the first year postpartum (Table 15) seem to indicate a move towards the prepregnancy diets. Over half of the postpartum adolescents (53.1 % ) indicated that the total amount of food consumed daily decreased after delivery. At least one-third of the postpartum adolescents indicated that they were consuming less milk (59.4%) and other dairy products
( 40.6% ); dried beans, peas, and legumes (35.9% ); vegetables (33% ); breads and cereals (35.9% ); sauces and gravies (37.5% ); fats and oils (39.1 % ); koolade
( 40.6% ); chocolate (34.4% ); and other sweets ( 42.2% ). Decreased consumption of dairy products, breads and cereals, dried beans and peas, fruits, and vegetables would explain some of the nutrient density differences between pregnancy and postpartum for calcium, riboflavin, ascorbic acid, vitamin A, and vitamin D. Most of the postpartum adolescents (79.7%) also reported taking fewer vitamin/mineral supplements after pregnancy.
110 Table 15. Adolescents' Self-reported Changes in Usage Patterns for Selected Food and Non-foodItems Postpartum vs. During Pregnancy.a,b
Category of Food/ Pregnancy vs. Post12artum Changes Non-food Items Less Same More
<------% Participants ------>
Total amount of food 53.1 34.4 12.5 Milk 59.4 26.6 14.1 Cheese, ice cream and other dairy products 40.6 39.1 20.3 Meats 23.4 42.2 34.4 Dried beans and peas 35.9 53.1 10.9 Vegetables 32.8 48.4 18.8 Fresh fruit and unsweetened fruitju ices 31.3 42.2 26.6 Sweetened fruits and juices 43.8 42.2 14.1 Breads and cereals 35.9 42.2 21.9 Sauces and gravies 37.5 43.8 18.8 Fats and oils 39.1 37.5 23.4 Spicy foods 21.9 37.5 40.6 Chips, nuts, and snack crackers 31.3 40.6 28.1 Coffee 9.4 78.lc 12.5 Tea 17.2 64.1 18.8 Soft drinks 9.4 29.7 60.9 Koolade 40.6 53.1 6.3 Sweets, except chocolate 42.2 42.2 15.6 Chocolate 34.4 37.5 28.1 Fast foods ( e.g., McDonalds) 20.3 23.4 56.3 Vitamin pills 79.7 20.3 0 Alcohol 0 73.4d 26.6 Cigarettes 1.6 56.3e 42.2
3N = 64 postpartum adolescents who comprise a subsample of all adolescents enrolled in AES-TN860: Factors Influencingthe Nutritional Health of Adolescents During and Post Pregnancy (1987-1992). bData were collected with semi-structured interviews using a modifiedfood frequency questionnaire (Appendix J). c64.l % reported that they never consumed coffee. d59.4% reported that they never consumed alcohol. e40.6% reported that they never smoked.
111 At least one-third of the adolescents at 12 months postpartum reported increased consumption of meats (34.4% ), spicy foods ( 40.6% ), soft drinks (60.9% ), and fast foods (56 .3%). Forty-two percent also reported increased use of tobacco after pregnancy.
Reported Reasons for Dietary Change After Pregnancy
As was true during pregnancy, a variety of endogenous and exogenous variables were identified as factors leading to increases (Table 16) and decreases
(Table 17) in the consumption/usage of specific foods and non-food substances.
The reasons cited for dietary changes after pregnancy indicate a concern about body weight. Such a concern is common in adolescents (97, 101, 104). "To control or lose weight" was cited 153 times as the reason for changing the amount of certain foods consumed. Adolescents indicated increasing consumption/usage of fruits and vegetables, coffee, tea, soft drinks, and cigarettes "to control or lose weight"; they also reported decreasing consumption of milk and other dairy products, dried beans and peas, sweetened fruits and juices, breads and cereals, fats, chips, nuts, and snack crackers, and sweets "to control or lose weight".
A number of reasons cited for postpartum dietary changes suggest that changes were made during pregnancy for the sake of fetal and maternal health, and that postpartum changes were simply a return to the status quo. For example
"no baby to worry about", "no need to worry about personal health now", and "no need to eat as nutritious now" frequently were stated as reasons for decreasing
112 Table 16. Adolescents' Endogenous and Exogenous Reasons for Increasing Consumption of Specific Groups of Food and Usage of Selected Non food Items Following Pregnancy.a,b,c
TOTAL AMOUNT OF FOOD number of subjects (n)=8; number of responses (nr)=lO
Endogenous reasons Exogenous reasons -eating doesn't make me -boredom (3) sick now(4) -increased appetite (3)
MILK n=9, nr= 10
Endogenous reasons Exogenous reasons -tastes different (7) -increased availability (1) -craving (1) -it's the only beverage that is available now (1)
CHEESE, ICE CREAM, AND OTHER DAIRY PRODUCT'S n=l3, nr=15
Endogenous reasons Exogenous reasons -doesn't make me -increased availability (7) sick now (1) -substitute for milk (3) -tastes different (1) -wasnot good for baby (1) -craving ( 1) -do not have to worry about weight now (1)
MEATS n=22, nr=27
Endogenous reasons Exogenous reasons -tastes different (9) -increased availability (3) -doesn't make me -substituted other foods sick now (7) when pregnant (2) -meat was too heavy -avoided during pregnancy during pregnancy (4) for health reasons (1) -health professionals' influences ( 1)
DRIED BEANS, PEAS, ANDLEGUMES n=7, nr=8
Endogenous reasons Exogenous reasons Unsure -doesn't make me -increased availability (5) (1) sick now (3) -tastes different (2)
113 Table 16 (Omtinued)
VEGETABLES n=12, nr=15
Endogenous reasons Exogenous reasons -doesn't make me -increased availability (5) sick now (3) -control or lose weight (2) -tastes different (2) -personal health (1) -craving ( 1) -more interest in them now (1)
FRESH FRUITSAND UNSWEETENED FRUIT JUICES n=17, nr=21
Endogenous reasons Exogenous reasons Unsure -tastes different (5) -control or lose weight (5) (2) -thirstier now (1) -increased availability (3) -quick and easy (2) -concern forpersonal health (1) -health professionals' influences (1) -good influenceon baby (1)
SWEETENED FRUITS AND JUICES n=9, nr=ll
Endogenous reasons Exogenous reasons -doesn't make me -control or lose weight (3) sick now (1) -quick and easy snack (3) -tastes different (1) -boredom (1) -increased availability (1) -don't have to worry about weight now (1)
BREADS AND CEREALS n=14, nr=15
Endogenous reasons Exogenous reasons Unsure -increased appetite (1) -quick and easy (4) (2) -tastes different (1) -increased availability (3) -don't have to worry about weight now (2) -snacking on these foods more( 1) -boredom (1)
SAUCES AND GRAVIES n=12, nr=13 Endogenous reasons Exogenous reasons -doesn't make me sick now (6) -increased availability (3) -tastes different (1) -don't have to worry about -craving (1) weight now (2)
114 Table 16 (Continued)
FATS AND OILS n=l5, nr=15
Endogenous reasons Exogenous reasons Unsure -doesn't make me sick -don't have to work about (1) now (5) weight now (3) -tastes different (3) -work at fast food restaurant (1) -no baby to worry about ( 1) -no one telling me to avoid it now (1)
SPICY FOODS n=26, nr=29
Endogenous reasons Exogenous reasons Unsure -don't make me sick -no baby to worry about ( 4) (1) now (22) -increased availability (2)
CHIPS, NUTS, AND SNACK CRACKERS n=18, nr=23
Endogenous reasons Exogenous reasons Unsure -tastes different (2) -increased availability (5) (1) -doesn't make me sick -snacking more (4) now (1) -no baby to worry about (4) -don't have to worryabout weight now (3) -wear braces now (1) -quick and easy (1) -no one telling me to avoid them now (1)
COFFEE n=8, nr=12
Endogenous reasons Exogenous reasons -need it to stay awake (2) -no one telling me to -doesn't make me sick avoid it now (3) now (1) -no baby to worry about (2) -thirstier now (1) -don't have to worry about health now (1) -increased availability (1) -control or lose weight (1)
115 Table 16 (Continued)
TEA n=12, nr=14
Endogenous reasons Exogenous reasons -thirstier ( 1) -avoided caffeine during -need it to stay awake (1) -pregnancy (5) -no one telling me to avoid it now (3) -control or loseweight (2) -habit (1) -no baby to worry about (1)
SOFTDRINKS n=41, nr=50
Endogenous reasons Exogenous reasons -thirstier (5) -no baby to worryabout (21) -tastes different (1) -no one telling me to avoid it now (9) -craving ( 1) -increased availability (5) -habit/addiction (4) -control or lose weight (2) -it's the only thing that is available (2)
KOOLADE n=4, nr=6
Endogenous reasons Exogenous reasons -thirstier (1) -inexpensive (3) -it's the only thing that is available (2)
SWEETS, EXCEPT CHOCOLATE n=lO, nr=12
Endogenous reasons Exogenous reasons Unsure -craving ( 1) -don't have to worry about weight (5) (1) -tried to eat healthier during pregnancy (2) -increased availability (2) -no one telling me to avoid it now (1)
116 Table 16 (Continued)
CHOCOLATE n=18, nr=23
Endogenous reasons Exogenous reasons Unsure -craving (6) -tried to eat healthier during pregnancy (6) (1) -tastes different (1) -don't have to worry about weight (4) -increased availability (3) -no one telling me to avoid it now (2)
FAST FOODS n=36, nr=41
Endogenous reasons Exogenous reasons -doesn't make me sick -"on the go" more (15) now (1) -work at fast food restaurant (10) -increased availability (7) -tried to eat healthierduring pregnancy (3) -lazy; don't want to cook (3) -easy (1) -don't need to watch weight now (1)
VITAMIN PILLS n=O, nr-0
ALCOHOL n=17, nr=19
Endogenous reasons Exogenous reasons Unsure -tastes different (2) -no baby to worry about now (11) (2) -doesn't make me sick -to "flush out" kidneys (1) now (1) -nerves (1) -party more now (1)
CIGARETTES n=27, nr=30
Endogenous reasons Exogenous reasons -no response given -no baby to worry about (21) -nerves, stress, habit (6) -increased availability (1) -control or lose weight (1) aN =64 postpartum adolescents who comprise a subsample of all adolescents enrolled in AES-TN860: Factors Influencing the Nutritional Health of Adolescents During and Post Pregnancy(1 987-1992). bData collected using semi-structured interview format (modified food frequency checklist Appendix J). Data analyzed using content analysis. cEndogenous = physiological reasons. Exogenous = all other reasons.
117 Table 17. Adolescents' Endogenous and Exogenous Reasons for Decreasing Consumption of Specific Groups of Food and Usage of Selected Non Food Items Following Pregnancy.
TOTAL AMOUNT OF FOOD number of subjects (n)=34; number of responses (nr)=52
Endogenous reasons Exogenous reasons -decreased appetite (30) -control or lose weight (15) -no cravings (1) -no time to eat regularly (4) -no pressure from family to eat (1) -don't think about food as much (1)
MILK n=38, nr=45
Endogenous reasons Exogenous reasons -tastes different (9) -no baby to worry about (13) -makes me sick now (2) -not worried about personal -no cravings (2) health now (12) -decreased appetite (1) -control or lose weight (3) -no pressure from family to eat (2) -no pressure from health professionals to eat (1)
CHEESE, ICE CREAM, AND OTHER DAIRY PRODUCTS n=26, nr=36
Endogenous reasons Exogenous reasons Unsure -no cravings (6) -control or lose weight (7) (1) -tastes different ( 4) -no baby to worry about (6) -decreased appetite (1) -not worried about personal -makes me sick (1) health now (5) -decreased availability (2) -no pressure from family to eat (2) -no pressure from health professionals to eat (1)
MEATS n=l5, nr=23
Endogenous reasons Exogenous reasons -decreased appetite ( 4) -no baby to worry about (5) -tastes different (1) -not worried about personal -no cravings (1) health now (4) -control or lose weight (4) -no pressure from family to eat (2) -decreased availability (1) -don't like to cook (1)
118 Table 17 (Continued)
DRIED BEANS, PEAS, AND LEGUMES n=23, nr=33
Endogenous reasons Exogenous reasons -tastes different (7) -no baby to worry about (5) -makes me sick (3) -no pressure from family to eat (5) -no cravings (1) -control or lose weight (4) -decreased appetite (1) -not worried about personal health now (4) -decreased availability (3)
VEGETABLES n=21, nr=28
Endogenous reasons Exogenous reasons -tastes different (3) -no pressure from family to eat (8) -decreased appetite (1) -no baby to worry about (6) -not worried about personal health now (5) -control or lose weight (3) -decreased availability (2)
FRESH FRUITSAND UNSWEETENED FRUIT JUICES n=20, nr=27
Endogenous reasons Exogenous reasons -no cravings (2) -no baby to worry about (8) -decreased appetite (1) -not worried about personal health now ( 4) -control or lose weight ( 4) -decreasedavailabilit y ( 4) -prefer sodas now (2) -no pressure from family to eat (1) -no pressure from health professionals to eat (1)
SWEETENED FRUITS ANDJUIC ES n=28, nr=40
Endogenous reasons Exogenous reasons -tastes different( 4) -no baby to worry about (7) -makes me sick (2) -control or lose weight (7) -no cravings (1) -not worried about personal -decreased appetite (1) health now ( 5) -prefer sodas now (2) -no pressure fromfamily to eat (2) -no pressure fromhealth professionals to eat (2) -no interest in them (1)
119 Table 17 (Continued)
BREADS AND CEREALS n=23, nr=36
Endogenous reasons Exogenous reasons Unsure -decreased appetite (5) -control or lose weight (12) (2) -tastes different (1) -skipping breakfast now (5) -decreased availability ( 4) -not worried about personal health now (2) -no baby to worry about (2) -no pressure from health professionals to eat (1) -prefer chips now (1) -tired of them (1)
SAUCES AND GRAVIES n=24, nr=27
Endogenous reasons Exogenous reasons -tastes different (4) -control or lose weight (10) -decreased appetite (3) -decreased availability (6) -no cravings (2) -skipping breakfast now (1) -not good forme (1)
FATS AND OILS n=25,nr=2 7
Endogenous reasons Exogenous reasons -tastes different (4) -control or lose weight (16) -no cravings (1) -don't want my baby to eat these foods (1) -decreased appetite (1) -don't like to cook (1) -makes me sick (1) -no interest in them (1)
SPICY FOODS n=l4, nr=16
Endogenous reasons Exogenous reasons -makes me sick (5) -control or lose -tastes different (4) weight (3) -no cravings (3) -not good for me ( 1)
120 Table 17 (Continued)
CHIPS, NUTS,AND SNACK CRACKERS n=20, nr=27
Endogenous reasons Exogenous reasons -decreased appetite (3) -control or lose weight (9) -tastes differentnow (3) -snacking less now (3) -no cravings (2) -tired of them (2) -no interest in them (2) -decreased availability (1) -don't want the baby to eat these foods (1)
COFFEE n=6, nr=9
Endogenous reasons Exogenous reasons -makes me sick (2) -not good for me (2) -don't need caffeine -control or lose weight (1) now (2) -health professionals' -tastes different (1) influences (1)
TEA n=ll, nr=16
Endogenous reasons Exogenous reasons -tastes different (3) -control or lose weight (3) -no cravings (2) -prefer sodas now (2) -don't need caffeine -not good for me (1) now (2) -health professionals' influences (1) -decreased availability (1) -no interest in this food (1)
SOFfDRINKS n=4, nr=S
Endogenous reasons Exogenous reasons -not good for me (2) -health professionals' influences (2) -control or lose weight (1)
KOOLADE n=26, nr=32 Endogenous reasons Exogenous reasons Unsure -tastes different (13) -prefer sodas now (7) (1) -no cravings (2) -lose or control weight (6) -less thirsty (1) -decreased availability (2)
121 Table 17 (Continued)
SWEETS, EXCEPT CHOCOLATE n=27, nr=31
Endogenous reasons Exogenous reasons -tastes different (7) -control or lose weight (16) -no cravings (5) -not good forme (1) -not tryingto gain weight (1) -no interest in these foods ( 1)
CHOCOLATE n=22, nr=28
Endogenous reasons Exogenous reasons -tastes different (5) -control or lose weight (16) -no cravings (5) -decreased availability (1) -not trying to gain weight (1)
FAST FOODS n=13, nr=16
Endogenous reasons Exogenous reasons -makes me sick (1) -control or lose weight (7) -no cravings (1) -easier to eat at home (4) -decreased availability (3)
VITAMIN PILLS n=51, nr-52
Endogenous reasons Exogenous reasons Unsure -makes me sick (1) -no prescription from doctor (26) (1) -don't need them (22) -no pressure from familyto take them (1) -lazy; forgetto take (1)
ALCOHOL n=O, nr=O
CIGARETTES n=l, nr=l
Endogenous reasons Exogenous reasons -no responsesgiven -less nervousnow (1)
3N =64 postpartum adolescents who comprise a subsample of all adolescents enrolled in AES-TN860: Factors Influencing the Nutritional Health of Adolescents During and Post Pregnancy (1987-1992). hoatacolle cted using semi-structured interview format (modified food frequency checklist - Appendix J). Data analyzed using contentanalysis. cEndogenous = physiological reasons. Exogenous = all other reasons.
122 consumption of milk and other dairy products, vegetables, meats, fruits, and
vitamin supplements, and they also were reported frequently as reasons for increased consumption of spicy foods, chips, nuts, and snack crackers, coffee, tea, soft drinks, chocolate and other sweets, fast foods, and alcohol.
These data also suggest that family and health professionals influenced dietary intake during pregnancy, and that lack of these same influences following delivery led to changes in the opposite direction. For example "no one telling me to avoid them now" was given as one reason for increasing consumption of fats and oils, chips, coffee, tea, soft drinks, and sweets during the first year postpartum.
Similarly, "no pressure from health professionals and/or family to eat the food" was cited sometimes as the reason for decreasing consumption of milk and other dairy products, meats, dried beans and peas, vegetables, and fruits.
At 12 months postpartum, 46.9% of the adolescents indicated that their appetites were lower after pregnancy than they were during pregnancy.
Postpartum cravings were reported less often as motivators of dietary change (12 responses vs. 118 responses during pregnancy). Taste changes following pregnancy, however, were reported fairly often (104 responses) as the reason for changes in food consumption. Taken together with the dietary changes reported during pregnancy, these data support the nutrient intake data and indicate that data collected in this study are accurate assessments of diets during pregnancy.
123 Appetite Compulsions
Pregnancy-Associated Cravings and Aversions
During pregnancy, 85.6% of the adolescents reported cravings for specific
foods and beverages, and 66% reported pregnancy-associated aversions. Only five
of the 97 subjects (5.2%) reported neither cravings nor aversions. These rates of
occurrence are similar to those reported in pregnant women (34, 35, 37-39).
Cravings for non-food substances were reported by 12.3% of the pregnant
adolescents. This was a slightly higher percentage than reported by Schneck et al.
( 6) and slightly lower than the percentage reported by Kaminetzky and associates
(105). Even so, white pregnant adolescents are not generally considered to be at risk for practicing pica ( 40, 41). Although the average number of cravings
reported by these adolescents was 2.8, a significant number reported cravings for
five or more foods. The same was true of aversions. The mean number of pregnancy-associated aversions was 1.07; however, 9.3% reported aversions for as many as three or more different foods. A frequency distribution of the number of
cravings and aversions reported by the 97 pregnant adolescents is shown in Table
18.
Cravings during pregnancy for a wide variety of foods and beverages were reported (Table 19). Those most often cited included sweets, especially chocolate, fresh fruit and fruitjuic es, pickles, pizza, ice cream, hamburgers, and spicy foods.
While cravings for odd food combinations ( e.g., pickles and ice cream) were
124 Table 18. Number of Cravings and Aversions Reported by Adolescents During and After Pregnancy.a,b
During Pregnanci Postpartumct
No. subjects (%) No. subjects (%)
Dietary cravings
None 14 (14.4) 33 (51.6) One or two 36 (37.1) 17 (26.6) Three to five 37 (38.1) 13 (20.3) More than five 10 (10.3) 1 (1.6)
Non-food cravings
None 85 (87.6) 57 (89.1) One 8 (8.2) 7 (10.9) Two 3 (3.1) 0 (0) Three 1 (1.0) 0 (0)
Aversions
None 33 (34.0) 42 (65.6) One 38 (39.2) 13 (20.3) Two to three 23 (23.7) 9 (14. 1) More than three 3 (3.1) 0 (0) aAdolescents are subsample of all adolescents enrolled in AES-TN860: Factors Influencing the Nutritional Health of Adolescents During and Post Pregnancy (1987-1992). bData collected using semi-structured interview format. cN = 97 pregnant adolescents. ctN = 64 postpartum adolescents.
125 Table 19. Dietary Cravings Reported by 97 Pregnant Adolescents.a,b,c
Meats and Protein Main Dishes Milk and DairyProducts High protein main dishes (15) Ice cream ( 15) Beef (14) Cheese (7) Fish/Shellfish (7) Milk (6) Chicken (5) Puddings (2) Peanut butter (3) Yogurt (1) Hotdogs (3) All meats (3) Vegetables Dried beans (2) Potatoes (5) Beef jerky (1) Salads (3) Ham (1) Tomatoes (3) Eggs (1) Cucumbers (3) Cabbage (2) Fruits and Fruit Juices Any vegetable (2) Any fresh fruit ( 6) Greens (1) Watermelon (5) Green peppers ( 1) Lemons (4) Carrots (1) Peaches (4) Sauerkraut (1) Strawberries (3) Any green vegetable (1) Apples (3) Asparagus ( 1) Bananas (3) Oranges (3) Breads and Cereals Fruit juices (3) Sandwich bread (16) Grapes (1) Chips (11) Passion Fruit (1) Pasta (4) Rhubarb (1) Fruit loops cereal (2) Cherries (1) Shredded wheat cereal (1) Bread sticks (1) Sweets Popcorn (1) Anything chocolate (30) Biscuits (1) Ice cream (15) Anything sweet ( 14) Fats and Oils Chocolate candy ( 4) Salad dressing ( 1) Donuts (3) Sour cream (1) Popsicles (3) Onion dip (1) Puddings (2) Mayonnaise ( 1) Chocolate syrup (2) Gravy (1) Any candy (2) Butter (1) Brownies (1) Cake (1)
126 Table 19 (Continued)
Beverages Miscellaneous Sodas (7) Pickles ( 19) Milk (6) Pizza (14) Fruit juices (3) Odd food combinations (13) Koolade (2) Spicy foods ( 11) Water (1) Any fast foods (6) Coffee (1) Burgers (6) Tea (1) Mexican foods ( 4) Italian foods ( 4) Mustard (2) Vinegar (2) Barbecue sauce ( 1) Catsup (1) Tabasco sauce (1) Steak sauce (1) a97 pregnant adolescents are a subsample of all adolescents enrolled in AES TN860: Factors Influencing the Nutritional Health of Adolescents During and Post Pregnancy (1987-1992). bData were collected using semi-structured interview format. csome cravings are listed under more than one category.
127 reported, these were the exceptions rather than the rule. Many of the adolescents' cravings (fruits and juices; sweets, especially chocolate; dairy products; salty snacks) were similar to those reported by pregnant adults (34-39). However, some cravings reported by the adolescents ( sweets, chips, ice cream, pizza, and fast foods) reflect common food choices of non pregnant adolescents (99, 195).
Non-food cravings included those for ice, dirt, alka seltzer, playdough, and cigarette butts. The most frequently reported pregnancy-associated aversions were to meats, eggs, and pizza (Table 20). These are similar to the aversions of pregnant adults, except that adults are more likely to report aversions to coffee and alcohol (34, 36, 37-39). However, most adolescents in this study denied consumption of either beverage prior to pregnancy.
Although it has been suggested that most cravings and aversions occur during the first 12 weeks of pregnancy ( 50), this did not appear to be true for these pregnant adolescents. When asked to identify the month during pregnancy when specific cravings first appeared, 40. 7% reportedly were first noticed during the first trimester of pregnancy, 45.5% became apparent during the second trimester of pregnancy, and 13.9% began during the last trimester. It is possible that some of the pregnant adolescents in this study were not aware that they were pregnant until after the first trimester, and therefore did not associate early dietary cravings with pregnancy.
At the time of the interview during the third trimester of pregnancy, most of the adolescents (78. 7%) indicated that they still experienced cravings for the
128 Table 20. Dietary Aversions Reported by 97 Pregnant Adolescents.a,b,c
Meats and Protein Main Dishes Vegetables Eggs (11) Potatoes (2) High protein main dishes (8) Lettuce (2) Beef (8) Greens (1) All meats ( 4) Spinach (1) Pork (4) Broccoli ( 1) Hotdogs and bologna ( 4) Cauliflower (1) Fish (4) Onions (1) Chicken (1) Peanut butter (1) Milk and dairy products Milk (3) Fruits and Fruit Juices Ice cream (3) Apple juice (1) Cheese (1)
Breads and cereals Beverages Pasta ( 4) Coffee (4) Bread (1) Soft drinks (3) Chips (1) Milk (3) Tea (2) Sweets and desserts Alcohol (2) Candy bars ( 1) Apple juice (1) Chocolate cake (1) Koolade (1) Anything chocolate (1) Miscellaneous Fats and oils Pizza (9) Mayonnaise ( 1) Pickles (5) Italian foods ( 4) Mexican foods (2) Cream of mushroom soup ( 1) Mustard (1) a97 pregnant adolescents are a subsample of all adolescents enrolled in AES TN860: Factors Influencing the Nutritional Health of Adolescents During and Post Pregnancy (1987-1992). bData were collected using semi-structured interview format. csome aversions are listed under more than one category.
129 reported foods. In 98.9% of cases, the pregnant adolescents reported eating the craved foods.
Non-food cravings were initially noted 41.2% of the time during the first trimester, 41.2% in the second trimester, and 17.6% in the third trimester of pregnancy. The 11 pregnant adolescents craving large quantities of ice reported giving into their cravings and consuming the ice, as did the one adolescent who craved dirt, but adolescents craving alka seltzer, playdough, and cigarette butts denied consumption of these items.
As was true of pregnancy-associated cravings, most aversions initially appeared during the first (57.3%) and second (34.0%) trimesters of pregnancy. Fewer aversions were first noted during the last trimester. In most cases (83.5% of the time), aversions continued from onset of pregnancy through the time of these third trimester interviews. Pregnant adolescents generally (87.8%) avoided the averse foods.
Beliefs About Pregnancy-Associated Dietary Cravings
The pregnant adolescents' responses to 13 belief statements about dietary cravings during pregnancy are shown in Table 21. The Cronbach's alpha coefficient established for this 13-item instrument was 0.79. On a scale of 0
( strongly disagree) to 4 ( strongly agree) median scores were always either 1 or 2, indicating that as a whole, the adolescents disagreed or had no opinion about the statements. Mean scores to individual statements ranged from 0.98 (If you don't
130 Table 21. Pregnant Adolescents' Responses to Belief Statements About Cravings During Pregnancy.a,b
Belief Strongly Strongly Median Statement Agree Agree Neutral Disagree Disagree Scores
<:------n ------:::>
I should eat what- ever I'm craving, my body must need it. 5 17 28 38 9 2
If you crave a food, your baby will like that food. 4 9 36 44 4 2
Craving ice means you're not getting enough of certain nutrients. 1 4 54 32 6 2
Eating lots of ice means your blood is low in iron. 0 6 62 23 6 2
When you are pregnant, you will crave pickles and ice cream. 4 14 15 48 16 1
Food cravings during pregnancy will determine your child's likes and dislikes in later life. 2 14 32 38 11 1
Cravings are what foods you need in your diet. 1 8 27 52 8 1
131 Table 21 (Continued)
Belief Strongly Strongly Median Statement Agree Agree Neutral Disagree Disagree Scores
<::------n ------::>
If you don't eat what you crave, when your baby is born, it will smack and lick its lips until given that food. 1 4 17 45 30 1
Give into your cravings or you will mark the baby. 1 1 24 47 24 1 Pregnant women crave things like starch and clay. 0 11 38 36 12 1
Food cravings in pregnancy can mark a child. 0 7 26 43 21 1
If you crave sweets it'll be a girl; if you crave salty foods, it'll be a boy. 0 0 31 38 28 1
If you crave sweets, girl; if you crave sour things, boy. 0 0 34 41 22 1
3N = 97 pregnant adolescents who comprise a subsample of all adolescents enrolled in AES-TN860: Factors Influencing the Nutritional Health of Adolescents During and Post Pregnancy (1987-1992). bBelief statements are a subset of those included in the Inventory of Beliefs, Carruth and Skinner, 1991.
132 eat what you crave, when your baby is born, it will smack and lick its lips until
given that food) to 1.7 (I should eat whatever I'm craving, my body must need it;
and Eating lots of ice means your blood is low in iron). Total scores ranged from
two to 32; maximum possible score was 52. The large numbers of neutral
responses to belief statements (Table 21) suggest that new information could sway the adolescents' opinions in either direction. Unlike people with strong beliefs who tend to resist ideas which conflict with their own, those without opinions are more easily convinced (196).
Total belief scores were not related to dietary intake, nor were they related to the number or type of cravings and aversions. Also, there were no differences in belief scores on the basis of age, education, school attendance, or marital status.
However, scores did differ according to socioeconomic status; adolescents with lower socioeconomic indices tended to have higher belief scores (F = 7.056; p =
.01).
Relationships Between Appetite Compulsions and Dietary Intake
Pregnant adolescents who reported cravings for sweets consumed significantly more sugar (147.5 vs. 120.0 gm; F = 5.57; p = .02) and more energy (2,623 vs. 2,214 kcal; F = 7.87; p = .006) than did those without similar cravings. Those adolescents reporting cravings for chips and other salty snacks consumed significantly more sodium (4,267 vs. 3,405 mg; F = 5.69; p = .02), more fat (122 vs. 96 gm; F = 6.28; p = .02), and more energy (2,922 vs. 2,364 kcal; F = 6.28;
133 p = .01) than did adolescents who reported no cravings for chips and other salty
snacks. While the difference was not statistically significant, there was also a
tendency for pregnant adolescents craving fruit to consume more ascorbic acid
(115 vs. 92 mg; F = 2.98; p = .09) than adolescents without such cravings. No
other differences in nutrient intake between adolescents craving and those not craving specific foods were found. Also, no relationships between appetite
compulsions (number and type) and age, education, marital status, school attendance, living arrangements, and socioeconomic status were identified.
The relationships between cravings for sweets and sugar and energy
consumption and the relationship between cravings for salty snacks and sodium consumption are important, because it has been hypothesized that physiological changes during pregnancy may lead to cravings for sugar and salt, in order to meet the needs of the mother and/or fetus (38, 47, 131). Conclusions about sodium are tenuous in this study; discretionary salt was not included in the dietary analysis as estimates of the amount of salt used by individuals often are unreliable (164).
Postpartum Appetite Compulsions
Appetite compulsions following pregnancy rarely have been studied.
Worthington-Roberts and associates (36) evaluated dietary cravings and aversions during pregnancy and for 12 months postpartum. They reported, that overall, appetite compulsions did not continue into the postpartum period at a rate higher than what might be expected in any nonpregnant population. In the current study,
134 postpartum cravings and aversions also occurred much less frequently than during pregnancy; they did, however, exist. A total of 75 cravings were reported by the
64 postpartum adolescents. Most of the cravings (70. 7%) were new cravings; they were not the same as those experienced during pregnancy. Foods craved most frequently during the postpartum period included chocolate, pizza, sodas, ice cream, french fries and "tater tots", pickles, chips, and beef (Table 22), all of which are generally considered to be foods commonly consumed by most adolescents. The postpartum adolescents most often were not able to identify specific reasons or causes for dietary cravings during the postpartum period, although eight adolescents (12.5%) stated that cravings occurred as the result of seeing the food, seeing television commercials about the food, or driving by fast food restaurants.
When asked if they experienced cravings associated with the menstrual cycle,
24 of 64 adolescents responded positively. The adolescents indicated that they experienced cravings for several days prior to (62.5%) and during (50%) menstruation. Cravings generally were for sweets ( 66. 7%) especially chocolate
(37.5% ), and chips (9.4% ). Similar cravings which may be related to hormonal changes have been reported by other researchers (36, 149-153).
Non-food cravings were reported by seven adolescents during the first year postpartum. In all cases, the craving was for large quantities of ice. Four of the seven adolescents also reported similar cravings during pregnancy.
135 Table 22. Dietary Cravings Reported by 64 Adolescents at 12-months Postpartum. a,b
Food Number of subjects
Chocolate 12 Pizza 8 Sodas 8 Ice cream 5 French fries/tater tots 5 Pickles 5 Chips 4 Beef 4 Hamburgers 3 Anything sweet 3 Mexican foods 3 Macaroni and cheese 2 Watermelon 2 Peaches 1 Strawberries 1 Cantaloupe 1 Any fresh fruit 1 Pork chops 1 McRib sandwiches 1 Cottage cheese 1 Coffee 1 Tea 1 Beer 1 Oreo cookies 1 a64 postpartum adolescents are subsample of all adolescents enrolled in AES TN860: Factors Influencing the Nutritional Health of Adolescents During and Post Pregnancy (1987-1992). bData were collected using semi-structured interview format.
136 Generally, aversions that were present during pregnancy disappeared following delivery (66. 7% ), and adolescents reported renewed consumption of the previously-avoided foods. Aversions during the postpartum period were reported by 33.4% of the adolescents vs. 66% during pregnancy. Most common aversions were to meats (11 adolescents), high-protein main dishes (five adolescents), milk
(five adolescents), eggs (three adolescents), and pickles (two adolescents). Many of the postpartum aversions (60.5 % ) were old aversions, the same ones experienced during pregnancy; the remaining 39.5% had appeared sometime during the first year postpartum. In all cases, adolescents denied consumption of the averse foods in their current diets.
Postpartum cravings and aversions ( number and type) were not related to demographic variables or to nutrient intake. Similar results in an adult population were reported by Worthington-Roberts et al. (36), the only other researchers known to study postpartum appetite compulsions.
Food Preferences
Eighty-one adolescents completed the sensory analysis of food preferences during the third trimester of pregnancy. At 12 months postpartum, 52 of those same adolescents repeated the analysis.
137 Food Preference Scores of Pregnant Adolescents
The minimum possible score for each food was zero ( dislike extremely), and the maximum possible score was 10 (like extremely). In most cases, actual scores spanned the entire range (Table 23). The only food that did not receive at least one score of 10 during pregnancy was skim milk. Foods not receiving a minimum score of zero included vanilla ice cream and ice milk, strawberry frozen yogurt, both chocolate puddings, salted chips, salted nuts, and saltine crackers; the highest minimum score recorded during pregnancy was 2.20 ( salted peanuts and saltine crackers).
If a score of 5.00 were considered neutral and any score above 5.00 represented some degree of tllike" and any score below 5.00 represented some degree of "dislike", 13 of the 16 foods could be classified as "liked" by the pregnant adolescents. The disliked foods included skim milk, unsalted chips, and unsalted nuts.
Paired food comparisons are shown in Table 24. During the third trimester of pregnancy, significant differences were found for whole vs. skim milk (p = .002), for salted vs. unsalted potato chips (p = .0003), for salted vs. unsalted peanuts (p = .0001), and for saltine vs. low salt crackers (p = .03). The differences in preference for the milk products are supported by several facts: (a) few of the pregnant adolescents reported consumption of skim milk on the dietary records/recalls; most typically consumed whole milk, and to a lesser extent 2% low-fat milk; (b) as part of the overall AES-TN860 study, when a group of 53
138 Table 23. Minimum and Maximum Food Preference Scores of Adolescents During the Third Trimester of Pregnancy and at Twelve Months Postpartum. a,b
Food During the Third Twelve Months Trimester of Pregnancy Postpartum Minimum Maximum Minimum Maximum Score Score Score Score
Whole milk 0 10.00 0 10.00 Skim milk 0 9.70 0 9.15 Vanilla ice cream 0.50 10.00 2.50 10.00 Vanilla ice milk 0.20 10.00 4.45 10.00 Strawberry ice cream 0 10.00 0.05 10.00 Strawberry frozen yogurt 0.50 10.00 1.20 10.00 Peaches in syrup 0 10.00 4.60 10.00 Peaches in juice 0 10.00 1.80 9.70 Chocolate pudding with added sugar 1.35 10.00 2.40 10.00 Chocolate pudding 2.00 10.00 0 10.00 Salted chips 1.30 10.00 1.90 10.00 Unsalted chips 0 10.00 1.60 9.90 Salted nuts 2.20 10.00 1.70 10.00 Unsalted nuts 0 10.00 0.35 10.00 Saltine crackers 2.20 10.00 1.90 9.30 Low salt crackers 0.10 10.00 0.30 10.00
aAdolescents completing sensory analysis are a subsample of all adolescents enrolled in AES-TN860: Factors Influencing the Nutritional Health of Adolescents During and Post Pregnancy (1987-1992). bData collected using sensory analysis (Appendix N). cscale: O=Dislike extremely; lO=Like extremely. dN=81 pregnant adolescents. eN =52 of the same adolescents at postpartum.
139 Table 24. Comparison of Paired Food Scores During the Third Trimester of Pregnancy and at Twelve Months Postpartum.a,b
Food Pair Third Trimester Twelve Months of Pregnancy Postpartum F value P F value P
Whole milk vs. skim milkc 9.56 .002 7.82 .005
Vanilla ice cream vs. c ice milk 0.76 NS 0.11 NS Strawberry ice cream vs. frozen yogurf 1.07 NS 0.05 NS Peaches in syrup vs. d peaches in juice 0.74 NS 0.13 NS Chocolate pudding with extra sugar vs. regular chocolate d pudding 1.04 NS 0.54 NS Salted vs. unsalted e potato chips 13.26 .0003 3.08 NS Salted vs. unsalted e peanuts 18.94 .0001 0.57 NS Saltines vs. e low salt crackers 4.73 .03 0.29 NS
8N = 52 adolescents completing sensory analysis during and after pregnancy; a subsample of all adolescents enrolled in AES-TN860: Factors Influencing the Nutritional Health of Adolescents During and Post Pregnancy (1987-1992). bData were collected using sensory analysis (Appendix N). cFood pairs differ in fat content. dFood pairs differ in sugar content. eFood pairs differ in salt content.
140 pregnant adolescents were asked to choose either skim or whole milk for a snack,
41 selected the whole milk and only 12 selected the skim milk; reasons for choosing the whole milk included "skim milk was too watery", "skim milk tastes bad", and "prefer the taste of whole milk"; only two of 12 adolescents chose skim milk because they preferred the taste.
The fact that ice milk and frozen yogurt were equally as acceptable as ice cream is a positive finding. In cases where weight gain is a concern, pregnant adolescents can satisfy their desires for ice cream by substituting similar products such as ice milk and yogurt, and in turn consume significantly less fat and calories.
These substitutions may be more realistic for adolescents who must limit fat intake than would be a substitution of skim for whole milk.
No differences in preference scores were found for foods containing the two levels of sugar. This was not expected because other researchers (47, 48, 54) have reported that sensitivity to sweet tastes in solution declines during pregnancy, and that preference for sweet tastes in solutions increases during pregnancy. The fact that no differences were seen in this study may reflect the difference in using foods vs. solutions for analysis.
The higher preference scores for salted vs. unsalted or low-salt foods during pregnancy also was consistent with the dietary intake data. Based on food records and recalls, less than 5% of the pregnant adolescents reported consuming the lower salt products during the four days that food intake was recorded/recalled.
Changes in sensitivity to and preference for salt during pregnancy have been
141 reported previously ( 47-49, 54). However, these studies were conducted on adult
rather than adolescent subjects.
Food Preference Scores of Postpartum Adolescents
Because of the incomplete follow-up of adolescents (35.8% of those who
completed sensory analysis during pregnancy did not repeat the process at one
year postpartum), and because of the incomplete block design, the number of
adolescents evaluating each food at 12 months postpartum varied from 16 tasting
the sweetened chocolate pudding to 38 tasting the vanilla ice cream. The range of
scores obtained at one year postpartum was smaller than during pregnancy.
Minimum scores were higher for 11 of the 16 foods, and maximum recorded scores were lower for four foods (Table 23).
Least squared means scores ( + standard errors) obtained at the postpartum analysis ranged fr om a high of 7.91 + 0.46 (vanilla ice milk) to a low of 2.67 +
0.46 (skim milk). Again, using a midpoint score of 5.00 as neutral, 14 of the 16 foods were "liked" by the postpartum adolescents who evaluated them. The only two "disliked" foods at this time were whole and skim milk. When scores obtained during and after pregnancy were compared statistically (Table 25), significant differences were found only for whole milk (p = .02), skim milk (p = .007), and salted nuts (p = .04). In each case, mean preference ratings were higher during pregnancy.
142 Table 25. Comparison of Adolescents' Food Preference Scores Obtained During the Third Trimester of Pregnancy and at Twelve Months Postpartum. a,b,c
Food Nd Food Preference Score (LS Means ± Standard Error) Third Trimester Twelve Months p of Pregnancy Postpartum
Whole milk 33 5.70 ± 0.37 4.41 ± 0.48 .02 Skim milk 36 4.16 ± 0.37 2.67 ± 0.46 .007 Vanilla ice cream 38 7.84 ± 0.37 7.71 ± 0.45 NS Vanilla ice milk 36 7.40 ± 0.37 7.91 ± 0.46 NS Strawberry ice cream 34 7.36 ± 0.37 6.59 ± 0.47 NS Strawberry frozen yogurt 31 6.85 ± 0.37 6.73 ± 0.49 NS Peaches in syrup 18 6.84 ± 0.47 7.50 ± 0.64 NS Peaches in juice 22 6.28 ± 0.47 7.21 ± 0.58 NS Chocolate pudding with added sugar 16 7.67 ± 0.47 7.44 ± 0.67 NS Regular chocolate pudding 25 7.01 ± 0.47 6.83 ± 0.54 NS Salted chips 21 6.83 ± 0.48 7.19 ± 0.59 NS Unsalted chips 19 4.45 ± 0.48 5.74 ± 0.62 .09 Salted nuts 21 7.42 ± 0.48 5.99 ± 0.59 .05 Unsalted nuts 23 4.57 ± 0.48 5.40 ± 0.56 NS Saltine crackers 21 5.42 ± 0.48 6.34 ± 0.59 - NS Low salt crackers 22 5.42 ± 0.48 5.90 ± 0.58 NS
3N = 52 adolescents completing sensory analysis during and after pregnancy; a subsample of all adolescents enrolled in AES-TN860: Factors Influencing the Nutritional Health of Adolescents During and Post Pregnancy (1987-1992). bData were collected using sensory analysis ( Appendix N). cscale: O=Dislike extremely; lO=Like extremely. dNumber of adolescents tasting each food during and after pregnancy.
143 The difference in preference for the milk products during the third trimester of pregnancymight be expected on the basis of information obtained on the modified food frequency questionnaire. Several ( 11% ) of the pregnant adolescents indicated that they were consuming more milk because it tasted better. Many of the adolescents (n = 63), however, also stated that milk consumption increased because they believed that more milk was required during pregnancy for the babies' health or because family and health professionals encouraged them to do so. Because preference includes much more than just taste, other factors such as health-related ideas and beliefs about the influence of nutrition during pregnancy may affect preference.
The difference in preference scores for salted nuts can be less easily explained.
Althoughthe preference for salted nuts was higher during than after pregnancy, this same trend was not identifiedfor salted chips and saltine crackers. The observed differencesmay well be due to chance, rather than to a real preference difference.
At 12 months postpartum, the only significantdiff erences in food pairs were found between whole and skim milk (p = .005). Again, however, foodrecords and recalls show that postpartum adolescents generally did not consume skim milk in their daily diets; most usually consumed whole and sometimes 2% low-fat milk.
144 CHAPTER V
CONCLUSIONS AND IMPLICATIONS
This study consisted of three components, an exploratory evaluation of factors affecting consumption of specific foods, an evaluation of appetite compulsions and their impact on diet, and a sensory analysis of preferences for specific foods; all were evaluated during the third trimester of pregnancy and again at 12 months postpartum. At first, these three components may appear to be unrelated concepts and to represent distinct areas of research rather than interdependent means of studying food-related behavior. However, each component provided information about factors influencingthe dietary intake of adolescents during and after pregnancy. Perhaps, the most important findingwas that most data in each component were consistent and supported by the dietary data.
For example, many adolescents stated that they increased their consumption of milk during pregnancy. Reasons forthis change included exogenous factors such as concern for personal and/or fetal health and family and/or health professionals' influences; reasons also included endogenous factors such as cravings for milk and changes in taste perception (i.e., milk tasted better) during pregnancy. In evaluating appetite compulsions, adolescents admitted consuming the foodsthey craved; a number of adolescents again indicated that
145 cravings for milk and dairy products resulted in increased consumption. In the
sensory analysis, preference scores for both whole and skim milk were significantly higher during the third trimester of pregnancy than at 12 months postpartum, suggesting that forone reason or another, milk was "liked" more during pregnancy.
A comparison of dietary data during and after pregnancy showed a statistical difference in calcium consumption; adolescents consumed about 40% more calcium during the third trimester of pregnancy than at 12 months postpartum.
While calcium in the diet can come from sources other than milk, this investigation showed minimal consumption of those foods by the adolescents.
Calcium consumption at 12 months postpartum was similar to data reported for non-pregnant adolescents in East Tennessee and other regions of the United
States.
Unfortunately, a direct comparison of the same group of adolescents before and during pregnancy is not practical because of the large sample size required for initial screening in order to provide a reasonable sample of pregnant adolescents to be studied, and because of the subsequent time involved for data collection on that representative sample. Therefore, indirect comparisons were used in this study; pregnant adolescents were asked to recall and compare the amounts of certain foods consumed during pregnancy to the amounts consumed prior to conception. In general, pregnant adolescents indicated greater overall consumption of food, especially milk and dairy products, fruits and vegetables, breads and cereals, and chocolate. All could serve to increase caloric intake
146 during pregnancy, and with the exception of chocolate, all could serve to increase nutrient intake and nutrient density. This information was consistent with the dietary data. The quality (nutrient density) of diets consumed by the pregnant adolescents in this study was greater than that reported in nonpregnant adolescents and similar to that of other pregnant adolescents (32, 181).
At 12 months postpartum, most participants indicated that they were consuming less food than during pregnancy. Particularly striking were the types of consumption changes made postpartum. Adolescents were most likely to decrease consumption of milk and dairy products, fruits and vegetables, breads and cereals, and to increase consumption of sodas, chips, and fast foods. The dietary data also supported these findings. The average postpartum diet was lower in calories, lower in nutrients, and in most cases, lower in nutrient density than the average of four days' dietary intake during the third trimester of pregnancy.
This study showed that most adolescents, like adults, experienced dietary cravings during pregnancy. In general, the adolescents in this study indicated that cravings for specific foods led to increased consumption of those foods. The most frequently reported pregnancy-associated dietary cravings included sweets, especially chocolate, pickles, pizza, and other fast foods. In addition, a number of cravings for dairy products, fruits, and some vegetables were reported. Cravings for non-food substances were reported by only 12.3% of the pregnant adolescents.
While few differences in nutrient intake of cravers vs. non-cravers of specific foods were found, this investigation did not truly assess increase in dietary intake due to
147 cravings because quantitative information about dietary intake prior to pregnancy was not collected.
Most of the pregnant adolescents also experienced aversions. The most common dietary aversions were to meats, pizza, and eggs. In general, the pregnant adolescents reported avoidance of the aversive foods throughout pregnancy.
At 12 months postpartum, some adolescents indicated that they had experienced appetite compulsions at some time after delivery. However, both cravings and aversions were reported by a smaller number of adolescents than during pregnancy. As was true during pregnancy, the adolescents indicated that cravings led to increased dietary intake and aversions led to decreased intake.
Cravings during the postpartum period generally were reported for sweets, chips, sodas, and pizza.
Food preference data collected during the third trimester of pregnancy showed that adolescents preferred whole milk over skim milk, and salted chips, nuts, and snack crackers over the unsalted versions. No difference in preference scores were seen for ice cream vs. yogurt or ice cream vs. ice milk, or for the products containing differing amounts of sugar. At 12 months postpartum, adolescents again preferred whole milk over skim, and there was a trend (p = .08) toward a higher preference for salted over unsalted chips. No other differences were identified.
148 The fact that there were no differences in preference for the ice creams and sugar products is important. Both during and after pregnancy, weight is a concern of many adolescents (95, 97, 101). Ice cream, especially, is a popular food choice of adolescents. If however, as this analysis suggests, adolescents like the low- and higher-fat products equally, they may be able to satisfy their tastes for certain foods (such as ice cream) with lower-fat, lower calorie products. When during and after pregnancy food preference scores were compared, significant differenceswere found for whole milk, skim milk, and salted nuts. In each case, scores were higher during pregnancy.
No correlation between preference scores and quantity of specific foods consumed during the third trimester of pregnancy and at 12 months postpartum were found. However, the dietary data were limited to four days at each data collection period. A quantitative food frequency questionnaire would have been best suited for this type of analysis but was not included in the current study because of time constraints and because the methodology used ( records and recalls) was more appropriate for the objectives of the overall study; the data collected using records and recalls also lends itself to comparing research data published about pregnant adolescents in other studies (See Table 9).
149 Implications for Health Care Providers
Nutritionists and other counselors in the health care professions should realize that many factors affect dietary intake, and some factors are beyond the control of pregnant adolescents. Economic and family situations affect availability, and in some cases, "healthy food choices" during pregnancy are less available than would be considered optimal for maternal and/or fetal health. Also, some dietary changes may be motivated by physiological factors, such as thirst and hunger.
However, adolescents do appear to be capable of internalizing and applying messages about nutrition during pregnancy. In many cases, the adolescents in this study indicated dietary changes "for the baby's health", or "for the mother's health" or even "because of health professionals' influences". The dietary data supported those changes. It is discouraging that few adolescents indicated dietary changes because the dietitian suggested it; however, it is likely that contact with dietitians was limited both during and after pregnancy. The manner in which prenatal health care systems are set up generally results in little contact time with dietitians.
Participants in this study, as a whole, made positive dietary changes during pregnancy. They also appeared to be interested in doing whatever was best for the baby. Many of the pregnant adolescents asked nutrition-related questions of the researchers, and when responding to questions, it was not uncommon to hear comments like, "I'm not sure if I should do this, but ....". Although this may have
150 been a biased group as noted earlier, it does appear that some adolescents are eager for information about improving food choices during and after pregnancy.
While the average diet consumed by both pregnant and postpartum adolescents was adequate in most nutrients, the mean values may obscure very low and very high intakes by individuals. Based on nutrient intake data, there were some adolescents who consumed extremely poor diets; in some cases, this could be attributed to the adolescents always feeling ill. However, not all dietary inadequacies can be explained by similar factors. As shown in this study, any number of variables affect dietary intake, and those variables should be explored fully with adolescent clients.
Based on this study, it appears that health professionals' messages about calcium have been internalized and applied by adolescents. Because many diets were low in folate, iron, zinc, magnesium, and vitamin B6, there appears to be a need for nutrition education messages that place emphasis on these nutrients.
Research Needs
The sample of adolescents studied in this investigation were white pregnant adolescents who were first seen during the third trimester of pregnancy and who lived within a 120 mile radius of Knoxville, Tennessee. The average age of the pregnant adolescents was 16.3 years, and the average socioeconomic level was low.
To determine whether this group of adolescents is unique, similar studies
151 (including appetite compulsions, food preferences, and reasons for dietary change during and after pregnancy) should focus on black and hispanic adolescents, adolescents from other regions of the country, younger adolescents, and adolescents from higher socioeconomic strata.
Dietary intake data and food preference data were collected during the third trimester of pregnancy and at 12 months postpartum. To determine whether the third trimester is different from the earlier months of pregnancy, data should be collected throughout gestation. It is possible that intakes of nutrients are higher (or lower) during the last trimester than during the previous two trimesters.
Because food preferences are influenced by many different factors including taste, and because pregnancy is a time of physiological and psychological change, it is also possible that preferences undergo modifications throughout the course of pregnancy.
The food preference analysis was conducted using 16 specific foods.
However, each adolescent evaluated only half of the foods. While a randomized incomplete block is a valid design, it is probably not as efficient (i.e., it provides less data) as a complete block design (where each subject evaluates each foods).
In this study, the incomplete block may actually have been the "best" design because of limited cognitive skills and attention spans of typical adolescents.
In the current study, there was no repetition of individual evaluations. It is possible that the day-to-day variability in preference within subjects would be significant enough that a repeated measures analysis would result in different
152 findings. The foods included in this analysis were selected because of their sugar, salt, and fat content. Because the participants in this study often indicated that fruits, juices, and raw vegetables tasted better during than prior to pregnancy, an analysis using these items might provide greater insight into the area of food preference changes during and after pernancy. Fruits and vegetables also would provide nutrients that were judged as inadequate in the diets of pregnant and postpartum adolescents in this study. Another area for future study might include sensory analysis of selected "bitter-tasting" foods, such as coffee, tea, meats, and cooked vegetables, because some pregnant women and adolescents report that these foods taste different during pregnancy. Avoidance of meats and vegetables also can lead to inadequate dietary intake.
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162 96. United States Department of Agriculture (1985) Nutrient intake: individuals in 48 states, year 1977-1978. Nationwide Food Consumption Survey, 1977-1978, Human Nutrition Information Service report no. 1-2, U.S. Government Printing Office, Washington, D.C.
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136. O'Rourke, D.E., Quinn, J.G., Nicholson, J.O. & Gibson, H.H. (1967)
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140. Maravilla, A.M. & Berk, R.N. (1978) The radiographic diagnosis of pica. Am. J. Gastroent. 70:94-99.
141. Williams, S.R. (1985) Nutritional guidance in prenatal care. In: Nutrition in Pregnancy and Lactation (Worthington-Roberts, B.S., Vermeersch, J. & Williams, S.R., eds.) 3rd ed., pp. 132-168, Mosby College Publishing, St. Louis, MO.
142. Hand, W.D. (1969) Folk beliefs from Boise, Idaho. West. Folklore 28:41-42.
143. Newman, L.F. (1969) Folklore of pregnancy: wives' tales in Contra Costa County, California. West. Folklore 28:112-135.
144. Edwards, C.H., McSwain, H. & Haire, S. (1954) Odd dietary practices of women. J. Am. Diet. Assoc. 30:976-981.
166 145. Palmer, J.L., Jennings, G.E. & Massey, L. (1985) Development of an assessment form: attitude toward weight gain during pregnancy. J. Am. Diet. Assoc. 85:946-949.
146. Hansen, R. & Langer, W. (1935) Uber geschmacksveranderungen in der schwangerschaft. Klin. Wochenschr. 14: 1173-1177.
147. Wade, G.N. & Zucker, I. (1969) Hormonal and developmental influences on rat saccharin preferences. J. Comp. Phys. Psy. 69:291-300.
148. Pike, R.L. & Yao, C. (1971) Increased sodium chloride appetite during pregnancy in the rat. J. Nutr. 101:169-176.
149. Gong, E.J., Garrel, D. & Calloway, D.H. (1989) Menstrual cycle and voluntary food intake. Am. J. Clin. Nutr. 49:252-258.
150. Dalvit, S.P. (1981) The effect of the menstrual cycle on patterns of food intake. Am. J. Clin. Nutr. 34:1811-1815.
151. Dalvit-McPhillips, S.P. (1983) The effect of the human menstrual cycle on nutrient intake. Physiol. Behav. 31:209-212.
152. Wright, P. & Crow, R.A. (1973) Menstrual cycle: effect on sweetness preferences in women. Harm. Behav. 4:387-391.
153. Pliner, P. & Fleming, A.S. (1983) Food intake, body weight, and sweetness preferences over the menstrual cycle in humans. Physiol. Behav. 30:663-666.
154. Wizenbaum, F., Benson, B., Solomon, L. & Brehony, K. (1980) Relationship among reproductive variables, sucrose taste reactivity and feeding behavior in humans. Physiol. Behav. 24: 1053-1056.
155. Blaustein, J.O. & Wade, G.N. (1976) Ovarian influences on the meal patterns of female rats. Physiol. Behav. 17:201-208.
156. Terhaar, M.B. (1972) Circadian and estrual rhythms in food intake in the rat. Harm. Behav. 3:213-219.
157. Morin, L.P. & Fleming, A.S. (1978) Variation of foodintake and body weight with the estrous cycle, variectomy, and estradiol benzoate treatment in hamsters. J. Comp. Physiol. Psycho!. 91:1-6.
167 158. Valenstein, E.S., Kakolewski, J.W. & Cox, V.C. (1967) Sex differences in taste preference for glucose and saccharin solutions. Science 156:942-943.
159. Dippel, R.L., Elias, J.W. & Yandell, L. (1983) Synthetic progestins and sweetness preference in intact female Sprague-Dawley rats. Physiol. Behav. 31:347-351.
160. Zucker, I. (1969) Hormonal determinants of sex differences in saccharin preference, food intake, and body weight. Physiol. Behav. 4:595-602.
161. Kenney, N.J. & Redick, J.H. (1980) Effects of ovariectomy and subsequent estradiol replacement on intake of sweet solutions. Physiol. Behav. 24:807-809.
162. Randall, E. (1982) Food preferences as a determination of food behavior. In: Social and Cultural Perspectives in Nutrition (Sanjur, D., ed.), pp. 123- 146, Prentice-Hall, Inc., Englewood Cliffs, NJ.
163. Kocher, E.C. & Fisher, G.L. (1969) Subjective intensity and taste preference. Percep. Mot. Skills. 28:735-740.
164. Pangborn, R.M. & Pecore, S.D. (1982) Taste perception of sodium chloride in relation to dietary intake of salt. Am. J. Clin. Nutr. 35:510-520.
165. Bartoshuk, L.M. (1978) The psychophysics of taste. Am. J. Clin. Nutr. 31:1068-1077.
166. Mattes, R.D. (1985) Gustation as a determinant of ingestion: methodological issues. Am. J. Clin. Nutr. 41:672-683.
167. Fischer, R., Griffin, F., England, S. & Garn, S.M. (1961) Taste thresholds and food dislikes. Nature. 191:1328.
168. Glanville, E.V. & Kaplan, A.R. (1965) Food preference and sensitivity of taste for bitter compounds. Nature. 205:851-853.
169. Jefferson, S.C. & Erdman, A.M. (1970) Taste sensitivity and food aversions of teenagers. J. Home Econ. 62:605-608.
170. Korslund, M.K. & Eppright, E.S. ( 1967) Taste sensitivity and eating behavior of preschool children. J. Home Econ. 59:168-170.
168 171. Anliker, J.A., Hooks, L.D. & Bartoshuk, L. (1989) The relationship of children's food preferences to their sensitivity to bitter taste. Society for Nutrition Education. Abstracts of Annual Meeting.
172. Scherr, S. & King, K.R. ( 1982) Sensory and metabolic feedback in the modulation of taste hedonics. Physiol. Behav. 29:827-832.
173. Nilsson, B. & Holm, A.K. (1983) Taste thresholds, taste preferences, and dental caries in 15-year olds. J. Dent. Res. 62: 1069-1072.
174. Shepherd, R., Farleigh, C.A. & Land, D.G. (1984) Preference and sensitivity to salt taste as determinants of salt-intake. Appetite 5:187-197.
175. Shepherd, R., Farleigh, C.A. & Land, D.G. (1984) The relationship between salt intake and preferences for different salt levels in soup. Appetite 5:281-290.
176. Larmond, E. (1976) Laboratory methods for sensory evaluation of food. Pub. no. 1637, Canada Department of Agriculture, Ottawa, Ontario, Canada.
177. Prell, P.A. (1976) Preparation of reports and manuscripts which include sensory evaluation data. Food Technol. 30:40.
178. Stone, H. & Sidel, J.L. (1985) Sensory Evaluation Practices, Academic Press, Inc., Orlando, FL.
179. Campbell, A.M., Penfield, M.P. & Griswold, R.M. (1979) The Experimental Study of Food, Houghton Mifflin Co., Boston, MA.
180. Hollingshead, A.B. (1976) Four Factor lndes of Social Status, Yale University Press, New Haven, CT.
181. White, A. & Skinner, J. (1988) Can goal setting as a component of nutrition education effect behavior change among adolescents? J. Nutr. Educ. 20:327-335.
182. Raker, M.R. (1979) The validity for a telephones food record. Unpublished M.S. Thesis, Pennsylvania State University, University Park, PA.
169 183. VanHorn, L.V., Gernhofer, N., Moag-Stahlberg, A., Farris, R., Hartmuller, G., Lasser, V.I., Stumbo, P., Craddick, S. & Ballew, C. (1990) Dietary assessment in children using electronic methods: telephones and tape recorders. J. Am. Diet. Assoc. 90:412-416.
184. SAS Institute, Inc. (1988) SAS User's Guide: Basics SAS Institute Inc., Gary, NC.
185. Stroupe, W.C. (1989) Why mixed models? In Applications of Mixed Models in Agriculture and Related Disciplines, Southern Cooperative Series Bulletin No. 343, pp. 1-8. Louisiana Agricultural Experiment Station, Baton Rouge, LA.
186. Achterberg, C. (1988) Qualitative methods in nutrition education evaluation research. J. Nutr. Educ. 20:244-250.
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195. Kenney, M.A., McCoy, J.H., Kirby, A.L., Carter, E., Clark, A.J., Disney, G.W., Floyd, C.D., Glover, E.E., Korslund, M.K., Lewis, H., Liebman, M., Moak, S.W., Ritchey, S.J. & Stallings, S.F. (1986) Nutrients supplied by food groups in diets of teenaged girls. J. Am. Diet. Assoc. 86:1549-1555.
196. Fleming, M. & Levie, W.H. (1978) Instructional Message Design Principles from the Behavioral Sciences. Englewood Cliffs, NJ.
171 APPENDICES APPENDIX A
RECRUITMENT TOOLS
1. Copy of the postcard that accompanied publicity posters.
I am interested in hearing more about the survey of adolescents conducted by The University of Tennessee. Please contact me to discuss the study in more detail.
Name ------Mailing Address ------
Alternate Telephone # ------Telephone # ------
173 APPENDIX A
RECRUITMENT TOOLS
2. Copy of referral form sent to health departments and schools.
YOU ARE NEEDED
You ARE NEEDED TO TAKE PART IN A STUDY ABOUT FOOD HABITS OF TEENS DURING AND AFTER PREGNANCY, You WILL BE PAID $5,00 FOR EACH OF 4 INTERVIEWS (4 INTERVI EWS = $20), IF YOU ARE INTERESTED IN KNOWING MORE ABOUT THE STUDY) YOU NEED TO GIVE PERMISS ION TO
_ TO GIVE YOUR NAME TO TEACHERS AT THE _A_G_E_N_C_Y / S___C_H _O-OL_ __ UNIVERSITY OF TENNESSEE) KNOXVILLE , UTK TEACHERS WILL CONTACT YOU TO TELL YOU MORE ABOUT THE STUDY AND SET UP THE FIRST INTERVIEW,
I AGREE THAT MY NAME MAY BE GIVEN TO TEACHERS AT THE UN IVERSITY OF TENNESSEE ,
NAME
ADDRESS
PHONE NUMBER
UNIVE RSITY OF TENNESSEE COPY
174 APPENDIX B
RECRUITMENT LETTERS
1. Copy of letter sent to potential subjects.
1nE l.JNNERSITY OF TENNESSEE KNOXVILLE
College of HumanEcology Dear
N ucricion and Thank you for your interest in hearing irore about our research. Food Science We are conducting a study of teenage girls during and after pregnancy. We ' re looking at eating habits , food preferences , · ideas about food , and Tv viewing habits .
Girls participating in the sOJdy are interviewed twice during the last three rronths of pregnancy and twice one yezr after the baby is bom. Each interview lasts betwee..11 45 minutes and one hour, and we pay $5 .00 per session. Although we are based in Knoxville , we have a !IDtor heme and can meet you in your town at any place convenient for you .
There are no risks to you or your baby associated with the study. You may ask questions du....---ing the intervie",,1, and you may contact us at The Unive=sity o� Tennessee (974-5445) at any time . 'You are tmder co obligation to participate , but it is very important thac we inte=view as mauy teenagers as possible. You can .help us leam !IDre abouc teens '. eating ha.bits during and after pregnancy. This information will be useful to health professionals who work with other girls·.in the future .
Please cons¥er helping us ! You can give us valuable inf01:mation thac we can t get anywhere else.
We are e..'1C losing a description of the study for you to share with your parents or guardians if you so choose. We will be contacting you by phone wichin . the next few days to discuss your participation.
Sincerely ,
Janet Pope , M.S. , R.D. Graduate SOldent
1215 West Cumberland Avenue, Room 229/Kno:cville, Tennessee, 3i996-1900/(615) 9i4-5+45,9i+.3491
175 APPENDIX B
RECRUITMENT LETTERS
2. Copy of letter sent to potential subjects to be shared with parents or guardians.
THE UNNERSITY OF TENNESSEE KNOXVILLE
Dear Parents : Your daughter has expressed an interest in hearing more about a research study conducted by the Department of Nutrition and Food Sciences at The University of Tennessee. We are evaluating factors affecting the
College of nutritional health of adolescents during and after Human Ecology pregnancy. These factors include things such as food intake patterns , food preferences , ideas about food, and Nutrition and television viewing habits . This is an important study , Food Science and we expect the results to be useful to health professionals counseling teens about appropriate nutrition. Should your daughter decide to participate , she will be interviewed twice during the final trimester of pregnancy and twice one year after the baby is born. Each interview will last about 45 minutes to one hour, and we will pay $5:oo per interview. We have a mobile laboratory so we can meet your daughter at a location convenient to her . There are no risks to your daughter or her baby associated with the study . Both you and your daughter are encouraged to ask questions . You may contact us at -974-5445. Your daughter is under no obligation to us ; it is entirely up to her to decide whether she wishes to participate. In addition, she may quit at any time. We think this is an important study, and we want .to interview as many girls as possible. We hope that your daughter will elect to help us . We will ·be contacting her by phone within the next few days to discuss her participation. If you have questions or concerns about the study, we would be happy to discuss them with you then or at any other time. We are willing to work with you in any way po�sible. Sincerely, J}._�� Dena Goldberg, M.S. , R.D. Graduate Student /jtl
1215 West Cumberland Avenue. Room 229/ Knoxville, Tennessee,37996-1900 /(615) 974-5445, 974-3491 176 APPENDIX C
LETTER OF CONFIRMATION FOR APPOINTMENTS
Date
Address
Dear
This letter is to confirm our appointment for__ d_ a_te__
We will meet you at --P�l .;;..;..ac..;;...;e;,..._ _ at __t=i _____m __ e . We look forward to seeing you then.
Sincerely,
Janet Pope Graduate Student
177 APPENDIX D
THREE MONTH FOLLOW-UP SURVEY
Dear
Hi! How are you and your new baby getting along? We hope that everything is going well for you both.
As you may recall, we talked about collecting more information from you at six months and one year after the baby was born. When your baby is about six months old, Wina Nevling, a graduate student at The University of Tennessee, will contact you to talk about your baby 's growth and eating habits. She wants to see both you and the baby at that time . You will receive $5.00 for that interview.
So that we can keep in touch, please take a few minutes to answer the following questions about you and your baby. Please tear off this letter, and answer the questions . After you have finished , fold the paper on the dotted line so that your answers are on the inside . Seal the paper by wetting the glue on the free edge of the paper. Return in the mail to us. No postage is necessary.
Thank you for providing this information.
Sincerely,
�(1p- �u� Janet Pope, M.S., R.D. Lisa Varner, M.S., R.D. Dena Goldberg, M.s. , R.O. Graduate Student Graduate Student Graduate Student
Code Number
1. What is your current name and mailing address?
2. What is your current phone number?
3. When did you have your baby? (month, day, and year )
4. What is your baby 's sex? Male Female
s. How much did your baby weigh at birth? ��-Pounds Ounces
6. How long was your baby at birth? Inches
7. How much did you weigh before you got pregnant? Pounds
8. How many pounds did you gain during your entire pregnancy?
Pounds
9. If you are married, what is your husband 's name?
178 APPENDIX E
COPY OF LETTER SENT TO SUBJECTS
AT 10 MONTHS POSTPARTUM
THE UNIVERSITT OF TENNESSEE KNOXVILLE
Date
College of Name Human Ecology Address Department of Nutrition Dear How are you? It's hard to believe that it's been almost a year since you had your baby . You may recall that when we saw you during your pregnancy, we agreed to contact you again after one year. It is now time to schedule your final interview with us. We do have a motor home , and we're willing to meet you at a location convenient to you . The interview will last about 1 1/2 hours . We would like to see both you and the baby at that time . As before, you will be paid $5.00 for the interview. In addition , we will ask you to fill out a couple of questionnaires at home and mail them in. You will be paid $5.00 ·for this too. We will contact you by phone within the next two weeks to set up an appointment. We are looking forward to talking with you again. Sincerely ,
Janet Pope Graduate Student /jtl
1215 Wes t Cumberland Avenue, Room 229/ Knoxville, Te nnesseeJi' 996-l900/(6I5) 974-5445, 974-3491 /FAX (615) 974-2617 179 APPENDIX F
STATEMENT OF INFORMED CONSENT
TN860 Code Number ----- Date ------
Statement of Infonned Consent
I understand that I am being asked to participate in a research project focused on beli efs and practices of adolescent females . I have had the fo llowing explained to me : 1. I wi ll be asked to respond to several questionnaires. These will contain questions about such things as my eating habits and food preferences, my ideas about food , and my television viewi ng habits. I also wi ll be asked to keep a record of the food I eat for two days. The amount of time required for me to provide this information will be about five hours, divi ded into two sessions duri ng pregnancy, and another three sessions after the baby is born . 2. I am also wi lling for the project personnel to get med ical information about my pregnancy (e.g., pre-pregnancy we ight, weight gai n, infant weight and gestational age , APGAR scores). 3. If I participate in this project, I wi ll get $5.00 for each of the interview sessions in which I complete all questionnaires. 4. I can choose whether I want to participate in the project, and I can quit at any time. If I do not participate or deci de to quit, there will not be any penalty other than not receiving the $5.00 per session . 5. There are no specific risks to me or my baby antici pated from my partici pation in the project. 6. The results from this project are expected to be helpfu l to professionals who wo rk with other teenagers. 7 . If I participate in this project, nobody other than project staff wi ll be given any information about me. Nobody wi ll be told anything in a way that would let them know I participated in this project. 8. If I have any questions, I can contact Dr. Betty Ruth Carruth or Dr. Jean Skinner, Department of Nutri tion and Food Sciences, The University of Tennessee, Kn oxville, Tennessee 37996- 1900, 974- 5445. Based on this information , I agree to participate in this project. Date ------Signatu re ------� Wi tness �------�
180 APPENDIX G
INFORMATION FORM
TN860 Code Number ------Date ------
Infonnati on Fonn
Name : ------Phone Number: Address:
Name and address of person(s) through whom client may be reached: Name : ------Phone Number: Address:
Name: ------Phone Number: Address:
Appointments: Date Time Place Comments
181 APPENDIXH
DEMOGRAPHICS AND BACKGROUND INFORMATION
TN860 Code Number ------Date ------
Demographics and Background Information
Age ___ Date of Birth ------Grade in school or last grade completed ___ Living Arrangements (check one): live wi th one parent live with both parents -- live with spouse -- live with parents and spouse -- live with other relative, specify: -- live in group home � other, specify:
1 Mother s Education: (check highest level ) Father's Education : (check highest level ) < 7th grade __ < 7th grade -- junior high school junior high school -- some high school -- some high school -- high school graduate � high school graduate -- some college or some col l ege or -- special ized training -- specialized training col lege graduate __ col l ege graduate -- graduate school or graduate school or -- professional training -- professional training __ not applicable not applicable 1 Spouse s Education : < 7th grade -- junior high school -- some high school -- high school graduate -- some col l ege or -- specialized training college graduate -- graduate school or -- professional training __ not applicable
I Mother s Occupation ------ Father's Occupation ------ I Spouse s Occupation ------
Estimated Date of Del i very ------ Doctor' s N ame ------ Pl ace of Del i very ------
182 APPENDIX I
FOOD RECALL/RECORD FORM
TN860 Code Number � � Date --�� � Record ��- Recall
Food Reca 11/R ecord Form
Food and Descri otion Amount 1st time food was eaten: time am _ pm_ where-- who , if anyone ate with you? watching TV � yes_ no _
2nd time food was eat� time am - pm where-- who, if anyone ate wi th you? watching TV , yes_ no�
3rd time food was eaten: time am _pm_ where-- who, if anyone ate with you? watching TV , yes_ no_
4th time food was eaten: time am _ pm,- where-- who , if anyone ate wi th you? watching TV , yes_ no_
5th time· food was eaten: time am - pm - where-- who , if anyone ate wi th you? wa tching TV , yes� no_
183 TN860
6th time food was eaten : time -- am _pm_ where who , if anyone ate wi th you? wa tching TV , yes no
7th time food was eaten : time -- am _pm_ where who , if anyone ate wi th you? watching _TV , ye s - no_
8th time food was eaten: time -- am _ pm _ where who , if anyone ate with you? watching TV , yes no_
9th time food was eaten : time am _pm_ '• where-- who , if anyone ate wi th you? watching TV , yes_ no_
If you ate more than 9 times use the back of this sheet. After completing this form, check yourself by answeri ng the following questions: 1. Have you listed everything you ate and drank during the day? 2. Did you include- the amount (i.e., 1 orange, 1 cookie, or 1 cup , 1 Tbsp., 1 tsp.) of each item consumed? 3. Did you descri be the way the foods were prepared (i.e., egg - scrambl ed , fried , poached)? 4. Did you describe, in as much detail as possible, the ingredients in casseroles, salads, sandwiches, soups, and other mixed dishes? 5. Did you remember to list everything you added to your food before you ate it (i.e. , sauces, gravies, butter, salad dressings) ? 6. Did you add anything to yo ur beverages (sugar, cream , milk, etc. )?
184 TN860 Code Number ------� Date Instructions for Completing Food Records Forms 1. Use the attached pages to record your food intake for two days . Please keep your records for ·· · and _. ------Do not change your normal eating pattern for those --,-days. 2. Record everything yo u eat and drink (except water) in each 24-hour peri od. 3. Remember to record the time you eat, where yo u eat, who you eat wi th, and if you are watching TV . 4. It is easier to complete this fo rm as you go, rather than wa iting until the end of the day. Carry the form wi th you , and -record each food when you eat it. 5. Descri be in as much detail as possible each food eaten , and indicate how it was prepared and served. a. Tel l whether fruits and vegetables are eaten raw or cooked. b. Identi fy preparation methods. Are foods fri ed , boi led, or steamed? c. Indicate brand names where possible (e.g., 2 c. Campbells Chicken and Noodle soup; 3 Mrs . Paul 's Fi sh Sticks wi th 1 Tbsp. catsup; 1 Burger Ki ng Whopper Junior with tomato, mustard, catsup, and pickles). d. For mixed dishes and sandwi ches, estimate and record amounts of major ingredients (e.g., Vegetable Salad - 1 c. lettuce, 1/2 c. tomato , 1/4 c. broccoli, 1/4 c. carrots , 1/2 egg, 1/4 c. Kraft reduced cal orie French dressing ; Ham and Cheese Sandwich - 2 slices whole wheat bread , 1 slice Mr. Turkey smoked turkey ham, 1 slice American cheese, 2 slices tomato, 1 leaf lettuce, 1/2 Tbsp. mayonnaise). e. Do not forget to record anything you .add to foods and beverages before eating (e.g. butter·, ·salad dressings , gravies, sauces , sugar, cream). f. Also , don 't forget to record foods eaten between meals and desserts eaten after meals. g. Sometimes you can get information from labels (e.g., 1 1/2 oz. milky way candy bar) . 6. Estimate as closely as possible the amounts of each food eaten. Use the fol lowi ng abbreviations for measures: cup = c. tablespoon = T. or Tbsp. teaspoon = t. or tsp. ounce - oz. 7. If you have questions , please contact Dr. Jean Ski nner, Dr. Betty Ruth Carruth, or Janet Pope , Department of Nutrition and Food Sciences , The University of Tennessee, Knoxville, TN 37996-1900, 974-5445.
185 APPENDIX J
FOOD FREQUENCY CHECKLIST
TN860 Code Number ---- Section I: Food Frequency Che ckl ist Date �------I. I am now going to read through a list of foods. For each food or group of foods, please tell me whether you eat the same amount as you did during the year before you were pregnant, whether you eat less of the food, or whether you eat more now that you are pregnant. If within a single food group, you consume more of some foods and less of others , let me know this too. Food Item Less, Same , Mo re Reason for (L, S, M) Chanoes Total Amount of Food
Mi lk
Cheese, ice cream, & other dairy products
Meats including fish & poultry
Dried beans and p eas like pinto beans
Vegetables
Fresh fruit & unsweetened juices Sweetened fruits & juices, includi ng canned fruit in syrup
Breads and cereals
Sauces and gravies
Fats (butter, sour cream, salad drsg.)
186 TN860
Food Item Less, Same , More Reason for ( L, S, M ) Chanqes Spicy foods
Chips , nuts, & snack c rac ke rs
Coffee , tea , and carbonated beverages (soft drinks ) Koolaid and other fruit-flavored dri nks
Sweets , except chocolate
Chocolate
Fast foods
Vitamin pi 11s
Beer, wine and other alcohol ic beverages
Cigarettes
2. Let 's go back to those foods that you are eating more of now that you are pregnant. As I list the food , tel l me , if you can, the reasons you are eating it more often. 3. Now, let's do the same for those foods that you eat less of now. As I read off the food , indicate the reasons that you eat the food less often now than before pregnancy.
187 APPENDIXK
APPETITE CHANGES INTERVIEW FORM
TN860 Code Number -�--- Date ------Appetite Changes Interview Fonn
Part II: Appetite Compulsions 1. Have you, at any time duri ng your pregnancy, experienced cravings for specific foods or beverages? By craving, I mean a strong urge to eat a food for which there was no previous excessive desire. No Yes (If answer to question 1 is yes, answer questions 2-5. If answer""'Tsrio , skip to question 6.) 2. What foods/beverages have you craved?
3. At what stage {or month) in your pregnancy did you fi rst notice these cravings? 4. Do you still have cravings for these foods/beverages? �� No Yes 5. Do you give in to your cravings? In other words , do you eat the foods/ beverages you crave? __ No Yes 6. Have you , at any time during your pregnancy , had cravings for thing's that you would not normally consider to be foods? No Yes {If answer to question 6 is yes, answer questions 7-10. If answer is no , �kip to question 11. ) 7. What have you craved? 8. At what stage (month) in your pregnancy did you first experience these cravings? 9. Do you still have cravings for these things? 10. Do you eat the things you crave? 11. Have you , at any time duri ng your pregnancy , experienced aversions fo r specific foods/beverages? By aversions, I mean extreme disl ikes for foods that you enjoy eating before pregnancy? __ No Yes 12. Toward what foods/beverages have you had aversions?
13. At what stage (or month ) in your pregnancy did you first have these aversions? 14. Do you still have these aversions? No Yes 15. Do you eat these foods/beverages? Comments:
188 APPENDIX L
BELIEFS ABOUT APPETITE COMPULSIONS
TN860 Code Number --- Date
Inventory About Food Beliefs During Pregnancy
Instructions: Please read each statement and check whether you agree or disagree. For example, do you agree or disagree with the statement, "Eating carrots gives you good eyesight?" If you agree, than check "Agree" column. If you have strong feelings about the statement, then check "Strongly Agree" column. If you have no belief about the statement check "No Opinion" column.
EXAMPLE Strongly No Strongly Belief Statement Al!ree Al!ree Ooinion Disa2ree Disa2ree
Eating carrots gives you good eyesight.
Now, begin to respond to the statements. If you have any questions ask the instructor to explain further. There are no right or wrong beliefs or responses. You may find that you have many cards in one or two columns and very few in other columns. This is okay because your beliefs are important to us.
Strongly No Strongly Belief Statement A2ree A�ree Ooinion Disal!ree Disa1rree
I should eat whatever I'm craving, my body must need it.
Give into your cravings or you will mark the baby.
If you crave a food, your baby will like that food.
Food cravings during pregnancy will determine your child's likes and dislikes in later life.
189 TN860
Strongly No Strongly Belief Statement Ae:ree Ae:ree Ooinion Disae:ree Disae:ree
When you are pregnant, you will crave pickles and ice cream.
Cravings are what foodsyou need in your diet.
If you crave sweets, it'll be a girl; if you crave salty foods, it'll be a boy.
Pregnant women crave things like starch and clay.
The baby gets what he/she needs first, the rest goes to the mother.
Food cravings in pregnancy can mark a child.
If you crave sweets, girl; if you crave sour things, boy.
Craving ice means you're not getting enough of certain nutrients.
If you don't eat what you crave, when you baby is born, it will smack and lick its lips until given that food.
190 APPENDIX M INCOMPLETE BLOCK DESIGN FOR SENSORY ANALYSIS
Block Four of Six "Fat Foods" Four of Ten Remaining. Foods
01 6 5 3 2 9 7 12 11
02 1 2 4 3 16 9 7 12
03 5 1 4 2 15 13 11 9
04 6 5 2 3 8 12 10 11
05 6 1 4 2 12 16 7 8
06 3 4 6 2 9 14 10 7
07 1 6 3 5 13 12 16 10 08 1 2 6 3 7 11 15 13
09 6 3 1 2 16 13 10 7
10 4 3 2 1 11 10 13 9
11 2 4 3 1 9 16 12 10
12 5 4 6 2 11 12 14 16
13 5 3 4 6 9 12 14 15 14 1 2 5 3 8 13 15 14
15 5 4 6 1 13 7 8 12 16 3 6 4 2 9 8 16 12
17 6 4 1 5 14 13 9 15
18 3 6 2 1 10 16 14 8
191 Block Four of Six "Fat Foods" Four of Ten Remaining Foods
19 5 6 3 4 12 14 9 8
20 4 6 1 5 13 12 9 16
21 1 3 4 5 12 13 15 9
22 4 2 6 5 9 14 8 15
23 3 1 2 4 15 8 9 13
24 4 6 3 2 7 16 13 11
25 4 2 1 3 16 15 8 13
26 5 1 2 6 9 10 7 11
27 6 5 3 1 7 11 9 16
28 4 6 3 2 7 10 12 14 29 6 1 2 5 9 10 15 11
30 6 1 4 5 10 12 16 15
31 3 2 4 6 12 9 14 11
32 4 1 2 6 15 10 8 13 33 1 6 4 5 9 16 12 11 34 5 1 3 6 12 7 15 16 35 1 4 3 2 12 8 7 10
36 2 1 6 5 14 8 15 16
192 Block Four of Six "Fat Foods" Four of Ten Remaining Foods
37 3 4 6 2 15 13 12 11
38 6 2 1 3 14 11 9 7 39 3 4 2 5 13 11 16 15
40 6 1 3 5 13 8 10 7
41 1 6 3 2 8 9 12 11
42 5 2 1 4 16 9 13 14
43 2 1 5 6 10 9 14 16
44 3 1 5 6 12 16 7 10 45 3 5 2 1 7 12 11 13
46 4 2 5 3 16 15 11 14 47 2 1 3 6 16 10 14 15
48 5 2 4 3 9 13 15 7
49 1 5 4 3 15 12 9 16
50 5 4 2 3 14 7 15 12 51 2 6 1 5 9 13 16 8 52 2 3 5 4 7 10 13 11 53 3 2 5 1 7 10 15 16
54 1 6 4 3 10 11 13 14
193 Block Four of Six "Fat Foods" Four of Ten Remaining Foods
55 2 5 4 6 15 11 10 16
56 5 1 4 3 12 11 15 14 57 4 2 5 6 14 13 11 16
58 6 5 3 4 16 9 13 10
59 6 4 5 2 7 16 8 9
60 4 1 6 3 12 13 11 8
61 3 2 1 5 10 9 7 12
62 5 6 4 1 8 14 13 11
63 5 4 3 2 8 11 10 16
64 1 2 5 4 12 15 13 8
65 3 2 1 5 8 7 13 16 11 66 5 2 6 1 8 7 9
67 1 5 3 4 8 13 14 12 11 68 6 4 3 5 10 8 7 69 3 1 4 6 9 14 16 7 70 4 3 6 5 16 14 8 7 10 71 1 5 6 3 15 14 13 11 10 72 2 6 3 5 14 12
1 94 Block Four of Six"Fat Foods" Four of Ten Remaining Foods
73 1 4 2 6 8 13 10 14
74 2 6 3 5 10 11 15 7 75 1 4 6 3 14 15 8 7
76 5 3 1 4 14 11 15 8
77 5 4 1 3 14 11 7 15 78 1 2 6 4 8 14 15 10
79 6 4 1 2 10 8 7 15 80 2 5 1 4 14 7 8 10
81 5 2 6 4 7 8 9 10
Efficiency 0.8999 0.8312
195 APPENDIX N
FOOD PREFERENCE ANALYSIS EVALUATION FORM
TN860 Code Number �----�--- Date
Food Preference Analysis Evaluation Fonn
Instructions: Please taste the four foods identified below, and eval uate them for preference. Indicate how much you like or dislike each product by drawing a vertical line across the scale in the area that you feel best describes your preferences.
Example : Suppose you are asked to taste and eval uate Food # 453. You taste the food and neither like nor dislike it. You indicate your feelings by marking the center of the line , midway between "dislike extremely" on the left side and "like extremely" on the right side.
Dislike Li ke Extremely Extremely
If you have any questions about this process, ask the instructor to explain further.
***At this time , please taste Food # ____ , and indicate your preference. ·
Di s'l i ke Like Extremely Extremely If you have additional comments about this food, please write your comments here .
***At this time, please taste Food # ____ , and indicate your preference.
Dis� i ke Li'ke Extremely Extremely If you have additional comments about this food , please write your comments here. ______
196 ***At this time, please taste Food #�-' and indicate your preference.
Dislike Like Extremely Extremely If you have additional comments about this food, please write your comments here. ------
***At this time, please taste Food #�-' and indicate your preference.
1 Di s l i ke Like Extremely Extremely If you have additional comments about this food, please wri te your comments here . ------
197 APPENDIX 0
POSTPARTUM CRAVINGS AND AVERSIONS INTERVIEW FORM
1N860 Subject Number ---- Date
INTRODUCTION: When we talked with you before, we asked about unusual cravings and aversions that you might have experienced during your pregnancy. Now, I'd like to ask about any cravings and aversions that you have experienced since your baby was born.
1. During your pregnancy, you said that you craved ______
Since you had your baby, have you craved these foods?______If yes, describe circumstances (when, how often, whether you eat the foods you crave, etc.) ------
2. Since you had your baby, have you had cravings for other foods or beverages? ___ If yes, what did you crave? ------Describe circumstances.------
3. Since your baby was born, have you had any cravings forthings not normally considered to be food? ___ If yes, what did you crave? Descnbe circumstances.------
4. Do you experience any cravings that you associate with your menstrual cycle? ___ If yes, what do you crave?
When do you have these cravings (before, during, after)?
5. When you were pregnant, you told us you have an aversion to
Do you still have these aversions? ___ If yes, do you ever eat these foods?
6. Since you had your baby, have you had aversions to other foods or beverages? ___ If yes, descnbe.
7. Are there any other foods that you enjoyed during your pregnancy that you cannot or will not eat now? ___ If yes, describe.
198 APPENDIX P
ADDITIONAL DIETARY DATA
1. Dietary intake of Pregnant Adolescents: Minimum and Maximum Values.a,b,c
Nutrient/Food Component Minimum Values Maximum Values
Kilocalories 1,174 4,717 Carbohydrate (gm) 134 305 Protein (gm) 36 222 Fat (gm) 44 99
Thiamin ( mg) 0.6 4.4 Riboflavin (mg) 0.8 7.3 Niacin (mg) 9 58 Vitamin B6 ( mg) 0.4 4.7 Palate (µg) 79 957 Vitamin B12 (µg) 0.9 27.5 Ascorbic acid (mg) 13 281 Vitamin A (IU) 1,216 15,055 Vitamin D (IU) 27 1,396 Vitamin K (µg) 4 923 Calcium ( mg) 348 4,764 Phosphorus ( mg) 611 4,701 Magnesium (mg) 75 721 Iron (mg) 5.8 47.4 Zinc (mg) 3 31 Iodine (µg) 0 1,196 Selenium (µg) 14 144
Sodium (mg) 1,320 6,860 Cholesterol ( mg) 74 799 Sugar (gm) 41 298 Dietary Fiber (gm) 3 23 a97 pregnant adolescents are a subsample of all adolescents enrolled in AES-TN860: Factors Influencing the Nutritional Health of Adolescents During and Post Pregnancy (1987-1992). bintake averaged over four days (2 records and 2 recalls). cintake does not include vitamin/mineral supplements.
199 APPENDIX P
ADDITIONAL DIETARY DATA
2. Dietary intake of Postpartum Adolescents: Minimum and Maximum Values. a,b,c
Nutrient/Food Component Minimum Values Maximum Values
Kilocalories 879 3,271 Carbohydrate (gm) 99 486 Protein (gm) 24 116 Fat (gm) 29 158
Thiamin (mg) 0.4 2.8 Riboflavin ( mg) 0.4 4.0 Niacin (mg) 6 42 Vitamin B6 (mg) 0.3 3.3 Folate (µg) 35 550 Vitamin B12 (µg) 0.9 9.4 Ascorbic acid (mg) 8 169 Vitamin A (IU) 494 10,180 Vitamin D (IU) 8 609 Vitamin K (µg) 0 371 Calcium ( mg) 198 1,515 Phosphorus ( mg) 436 2,082 Magnesium (mg) 42 327 Iron (mg) 3.7 28.3 Zinc (mg) 3 29 Iodine (µg) 0 335 Selenium (µg) 9 119
Sodium (mg) 1,091 5,235 Cholesterol ( mg) 63 571 Sugar (gm) 5 372 Dietary Fiber (gm) 1 18 a57 postpartum adolescents are a subsample of all adolescents enrolled in AES-TN860: Factors Influencing the Nutritional Health of Adolescents During and Post Pregnancy (1987-1992). bintake averaged over four days (2 records and 2 recalls). cintake does not include vitamin/mineral supplements.
200 APPENDIX P
ADDITIONAL DIETARY DATA
3. A Description of Dietary Intake of Pregnant Adolescents Based on Percentile Ranks Associated with Meeting the Recommended Dietary Allowances.a,b,c
Percentage of Participants Nutrient s33.3 % 33.4 to 66.8 to > 100% RDA RDAd 66.7% 100% RDA RDA
Kilocalories 0 12.4 48.5 39.2 Protein 0 3.1 14.4 82.5 Thiamin 0 4.1 26.8 69.1 Riboflavin 0 4.1 14.4 81.4 Niacin 0 3.1 24.7 72.2 Vitamin B6 7.2 34.0 42.3 16.5 Folate 11.3 46.4 26.8 15.5 Vitamin B12 0 1.0 7.2 91.8 Ascorbic acid 3.1 19.6 15.5 61.9 Vitamin A 1.0 13.4 24.7 60.8 Vitamin D 19.6 27.8 24.7 27.8 Vitamin K 8.2 22.7 13.4 55.7 Calcium 2.1 19.6 32.0 46.4 Phosphorus 0 5.2 22.7 72.2 Magnesium 2.1 34.0 38.1 25.8 Iron 21.6 68.0 7.2 3.1 Zinc 5.2 41.2 40.2 13.4 Iodine 27.8 26.8 5.2 40.2 Selenium 6.2 21.6 37.1 35.1
3N =97 pregnant adolescents who comprise a subsample of all pregnant adolescents enrolled in AES-TN 860: Factors Influencing the Nutritional Health of Adolescents During and Post Pregnancy (1987-1992). bDietary intake is averaged over four days (2 records and 2 recalls). cDietary intake does not include vitamin/mineral supplements. dRecommended Dietary Allowances for Pregnancy, 1989.
201 APPENDIX P
ADDITIONAL DIETARY DATA
4. A Description of Dietary Intake of Postpartum Adolescents Based on Percentile Ranks Associated with Meeting the Recommended Dietary Allowances.a ,b,c
Percentage of Participants Nutrient s33.3% 33.4 to 66.8 to > 100% RDA RDAd 66.7% 100% RDA RDA
Kilocalories 0 17.5 42.1 40.4 Protein 0 1.8 15.8 82.5 Thiamin 0 6.2 28.1 61.4 Riboflavin 1.8 12.3 24.6 61.4 Niacin 0 8.8 28.1 63.2 Vitamin B6 8.8 36.8 24.6 29.8 Folate 7.0 22.8 35.1 35.1 Vitamin B12 0 5.3 10.5 82.5 Ascorbic acid 12.3 15.8 35.1 36.8 Vitamin A 15.8 38.6 21.1 24.6 Vitamin D 50.9 31.6 14.0 3.5 Vitamin K 31.6 22.8 7.0 38.6 Calcium 12.3 47.4 21.1 19.3 Phosphorus 0 22.8 33.3 43.9 Magnesium 14.0 56.1 26.3 3.5 Iron 3.5 43.9 26.3 26.3 Zinc 5.3 42.1 29.8 22.8 Iodine 59.6 12.3 12.3 15.8 Selenium 8.8 38.6 35.1 17.5
3N = 57 postpartum adolescents who comprise a subsample of all pregnant adolescents enrolled in AES-TN860: Factors Influencing the Nutritional Health of Adolescents During and Post Pregnancy (1987-1992). bDietary intake is averaged over four days (2 records and 2 recalls). cDietary intake does not include vitamin/mineral supplements. dRecommended Dietary Allowances for nonpregnant female adolescents, 1989.
202 APPENDIX P
ADDITIONAL DIETARY DATA
5. Percentages of Adolescents Consuming Diets Providing Less Than Two-thirds of the Recommended Dietary Allowances During and After Pregnancy.a,b,c,d
Nutrient During Pregnanct After Pregnancyf
Kilocalories 12.4 17.5 Protein 3.1 1.8 Thiamin 4.1 6.2 Riboflavin 4.1 14.1 Niacin 3.1 8.8 Vitamin B6 41.2 45.6 Folate 57.7 29.8 Vitamin B12 1.0 5.3 Ascorbic acid 22.7 28.1 Vitamin A 14.4 54.4 Vitamin D 47.4 82.5 Vitamin K 30.9 54.4 Calcium 21.7 59.7 Phosphorus 5.2 22.8 Magnesium 36.1 70.1 Iron 89.6 47.4 Zinc 46.4 47.4 Iodine 54.6 71.9 Selenium 27.8 47.4 aAdolescents are subsample of all adolescents enrolled in AES-TN 860: Factors Influencing the Nutritional Health of Adolescents During and Post Pregnancy (1987-1992). bDietary intake averaged over four days (2 records and 2 recalls). cDietary intake does not include nutritional supplements. dRecommended Dietary Allowances (1989) are higher for pregnant adolescents than for nonpregnant adolescents. Exceptions include vitamin A, vitamin D, calcium, and phosphorus. eN = 97 pregnant adolescents. tN = 57 postpartum adolescents.
203 VITA
Janet Faye Pope attended primary and secondary schools in Zachary,
Louisiana, and graduated from Zachary High School in 1977. She received a
Bachelor of Science degree in dietetics and a Master of Science degree in
Institution Management from Louisiana Tech University. Janet has worked as a clinical dietitian in Shreveport, Louisiana, and as a clinical coordinator/instructor in the Coordinated Undergraduate Program (CUP) in dietetics at Louisiana Tech
University.
In September 1987, she entered graduate school at The University of
Tennessee, Knoxville. While there, she worked as a graduate assistant and as a graduate research assistant in the Department of Nutrition. Requirements for the
Doctor of Philosophy degree were completed in August, 1991.
Following graduation, Janet Faye Pope will return to Louisiana Tech
University, where she will be employed as an Assistant Professor of Nutrition and
Dietetics in the College of Human Ecology.
204