ENERGY BALANCE, HEALTH AND FECUNDITY AMONG BHUTIA WOMEN OF GANGTOK, SIKKIM, INDIA DISSERTATION Presented in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy in the Graduate School of The Ohio State University By Sharon R. Williams, M.A. * * * * * The Ohio State University 2003 Dissertation Committee: Dr. Douglas E. Crews, Advisor Approved by Dr. Ivy L. Pike . Dr. Paul W. Sciulli Advisor Department of Anthropology Dr. Gillian H. Ice ABSTRACT Health is a complex construct dependent on socio-cultural, economic and biological factors. The concept of health is very complicated; the expression of health is the result of the interaction of many biological, economic and cultural factors and includes both psychological and biological well-being. Health is not static. Humans are plastic, able to respond both behaviorally and biologically to stressors that threaten their well-being. The range of adaptive responses is highly variable and has long been an area of interest to Anthropologists. Human life history responds to stressors. Among women, the reproductive span is particularly sensitive to the environment. Fertility and its biological correlate fecundity are responsive to external stressors and often reflect the health and well-being of women in their environment. This research documents how differences in social settings, health, physical environment and biology interact and affect urban Bhutia women in Sikkim, India and contribute to the low fertility in this population. Individual variables such as nutrition, workloads and health have been found to significantly influence female fecundity by altering the levels of the hormones that make reproduction possible. While the contributions of these individual factors have been studied in detail, very little is known about the interactive effects of these three variables. Moreover, these three variables are ii significantly impacted by the changes associated with economic and social development and urbanization. Results of this study show that seasonal climatic variation significantly affects urban Bhutia women, their health and well-being. Measurements of energy balance, health, psychosocial stress and fecundity reflect changes in environment. However, responses of these variables to seasonal stressors were not consistent. Seasonal patterns in changes in energy balance, health status and fecundity were unique. Results of this study suggest that health measures influenced by anthropometric measures were not the ones impacting measures of fecundity in this sample of Bhutia women. The complex interactions between biology, behavior and environment and their influence on health and reproduction are reinforced by the results presented here. iii To Dan Thank you for of your love, support, patience and understanding. iv AKNOWLEDGMENTS First I need to thank Dr. Barun Mukhopadhyay, without whom this project would have not existed. Both Dr. Barun and Susmita provided invaluable logistical, methodological, ideological, and emotional support during my year in India. I would like to thank my very wonderful associates in the field, Bhupal, Tsultim, Tseten, and Sangay who made the fieldwork enjoyable and productive. I also need to thank Dr. B.B. Rai of the Sikkim Voluntary Health Association for his assistance. And, of course, I need to thank the wonderful women who participated in this study without whom there would be no dissertation. Back at home, I wish to thank my mentors and friends, Dr. Gillian Ice and Dr. Ivy Pike for their support, patience and the time to read and comment on the endless drafts of this dissertation. I also need to thank my advisor, Dr. Douglas E. Crews for all of the opportunities he has provided for me over the past several years. And last, but not least, my family and friends for all of their support. v VITA January 29, 1972 ………….……………… Born – Kenton, Ohio 1994 ……………….……………………… B.S. Molecular Genetics, The Ohio State University 1996 …………………………….……….... M.A. Anthropology, The Ohio State University 1995 – 1996 …………………………….… Graduate Research Associate, The Ohio State University 1996 – present ……………………….…… Graduate Teaching Associate, The Ohio State University PUBLICATIONS Williams SR. “Determinants of Low Fertility among Urban Bhutia Women in Sikkim, India.” American Journal of Human Biology. 2003;15(2):290 Vallianatos H and Williams SR. “Comparison of breast feeding practice in two urban north Indian populations.” American Journal of Human Biology. 2002; 14(1):134. Williams SR and Pike IL. “What does love have to do with it? Perceived stress levels and health in love marriages vs. arranged marriages in a tribal population of India.” American Journal of Human Biology. 2002;14(1):136. Williams SR, Pike IL, and Sansbury L. “Hunger, illness and hard work: Turkana women’s cortisol levels and perceived stress.” American Journal of Human Biology. 2000; 12(2):269. vi Williams, SR, IL Pike, CL Patil, and LB Sansbury. 2000. Hunger, illness, and hard work: Turkana women's cortisol levels and self-perceived stress. American Journal of Human Biology. 2000;12(2):272. Crews, DE and Williams SR. Molecular Aspects of Blood Pressure Regulation. Human Biology. 1999; 71(4): 475-503. Williams SR, Fitton LJ and Crews DE. “Seasonality of Births among the Cofan of Ecuador. American Journal of Human Biology. 1999; 10(1):138. FIELDS OF STUDY Major Field: Anthropology Specializations: Human Population Biology Biocultural Anthropology Reproductive Ecology vii TABLE OF CONTENTS Page Abstract ………………………………………………………………………………. ii Dedication ……………………………………………………………………………. iii Acknowledgments ……………………………………………………………………. iv Vita …………………………………………………………………………………... v List of Tables ………………………………………………………………………… vii List of Figures ……………………………………………………………………….. xiii Chapters: 1. Introduction …………………………………………………………………….. 1 1.2 Fertility and Fecundity …………………………………………………….. 3 1.2.1 Intermediate and proximate determinants of fertility ………………. 4 1.2.2 Menarche, menopause and the female fertile period ……………….. 7 1.2.3 Sources of variation within the fertile period ………………………. 9 1.3 Reproductive Ecology …………………………………………………….. 12 1.3.1 Physiological mechanisms for reproduction and the menstrual cycle ……………………………………………………………….... 13 1.3.2 Reproductive response to stressors …………………………………. 16 1.4 Stressors affecting fertility in urban populations … ……………………... 24 1.5 The Bhutia ………………………………………………………………… 25 1.6 Hypotheses ………………………………………………………………... 28 2. Background: Situating Bhutia Women ………………………………………… 29 2.1 Introduction ………………………………………………………………… 29 2.2 Women and fertility in India ……………………………………………….. 29 2.2.1 Population/birth control policies ……………………………………. 29 2.2.2 Fertility rates and trends in India …………………………………… 31 2.2.3 Status of women in India …………………………………………… 33 2.3 Sikkim …………………………………………………………………….... 39 2.3.1 Geographical location ………………………………………………. 39 2.3.2 Environment ……………………………………………………….... 40 viii 2.3.3 Politics, history and populations ……………………………………. 42 2.3.4 Development of the state …………………………………………… 43 2.3.5 Health status, demography and fertility of Sikkim …………………. 44 2.3.6 Health in Sikkim …………………………………………………… 45 2.3.7 Status of women in Sikkim ……………………………………….... 47 2.4 Bhutia Women …………………………………………………………… 50 3. Sample and Methods ……………………………………………………………. 52 3.1 Research design ……………………………………………………………. 52 3.2 Study population …………………………………………………………… 53 3.2.1 Sample selection and characteristics ..……………………………..... 54 3.3 Education and occupation ………………………………………………….. 55 3.3.1 Household characteristics …………………………………………... 57 3.3.2 Marriage and Family ………………………………………………... 58 3.4 Data collection techniques ………………………………………………….. 63 3.4.1 Overview ……………………………………………………………. 63 3.4.2 Procedures …………………………………………………………... 63 3.5 Statistical analysis ………………………………………………………….. 71 4. Results I: energy balance and seasonality ……………………………………… 72 4.1 Introduction ………………………………………………………………… 72 4.1.1 Body composition of the sample ……………………………………. 72 4.2 Measures of energy balance ………………………………………………... 75 4.3 Seasonal changes in measures and components of energy balance ………... 77 4.3.1 Large scale changes in energy balance ……………………………… 77 4.3.2 Changes in anthropometric measurements ………………………….. 83 4.3.3 Anthropometric indices ……………………………………………… 87 4.4 Summary …………………………………………………………………… 90 5. Results II: Energy Balance and Fecundity ……………………………………. 91 5.1 Introduction ………………………………………………………………… 91 5.2 Measures of fertility and fecundity ………………………………………… 92 5.2.1 Measures of population fertility …………………………………….. 92 5.2.2 The menstrual cycle ………………………………………………… 92 5.2.3 Lutenizing hormone (LH) and Follicle Stimulating Hormone (FSH) ………………………………………………………………… 97 5.3 Measures of health status ………………………………………………….. 98 5.3.1 Health history ………………………………………………………. 98 5.3.2 Anemia and hemoglobin levels …………………………………….. 100 5.4 Seasonal measures of health ………………………………………………. 102 5.5 Energy balance and fecundity ……………………………………………... 113 5.5.1 Predictors of average menstrual cycle length ……………………… 113 5.6 Energy balance and health status …………………………………………. 121 5.7 Health and fecundity ………………………………………………………. 125 5.8 Summary ………………………………………………………………….. 130 ix 6. Results III: social wellbeing and socioeconomic status ……………………….. 131 6.1 Introduction ……………………………………………………………….. 131 6.2 Socioeconomic status ……………………………………………………... 132 6.2.1 Measures of socioeconomic status …………………………………. 132 6.2.2 Socioeconomic index and SES rank ……………………………….. 136 6.3 Social well-being …………………………………………………………. 137