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CHAPTER 17 and Maternal Mental and Physical Health

JENNIFER H AHN-HOLBROOK,CHRIS DUNKEL S CHETTER, AND M ARTIE H ASELTON

INTRODUCTION optimal health benefits to the and . Despite these guidelines, recent esti- Expectant are inundated with mates are that while 70% of mothers initiate information about the benefits of breastfeed- breastfeeding after the birth of their child, ing for their babies but are often poorly only 13.5% of in the United States are informed about the consequences - exclusively breastfed for 6 months (Centers feeding has for their own mental and physi- for Disease Control and Prevention, 2011a). cal health. Women know about the Deciding how an will be fed is a potential benefits of breastfeeding for the complex decision involving various social, baby’s immune function and intellect psychological, emotional, and environmen- (Kramer et al., 2001; Kramer et al., 2008), tal factors (Arora, McJunkin, Wehrer, & but mothers could also be asking themselves: Kuhn, 2000). In order of importance, the What about me? A deep desire to breastfeed top five reasons women give for deciding to an infant is not shared by every mother. In breastfeed are (1) its benefits for the infant’s fact, even before the advent of bottles and health, (2) that it is “natural,” (3) to formula, many affluent women avoided strengthen bonding with their infant, breastfeeding altogether by paying poorer (4) convenience, and (5) benefits for their women to do it for them in an arrangement own health (Arora et al., 2000). By contrast, called wet-nursing. As the anthologist Sarah the top five factors that discourage breast- Hrdy (1992) noted, “during the heyday of feeding are (1) opposition by the baby’s wet-nursing at the end of the 18th century father, (2) concerns that the baby is not . . . up to ninety percent of infants born in getting enough milk, (3) the need to return urban centers such as Paris and Lyon were to work, (4) discomfort while breastfeeding, nursed by women other than their biological and (5) the misconception that breastfeeding mother” (p. 415). will adversely change the appearance of the Today, the World Health Organization (Arora et al., 2000). Given the level of (2009) recommends exclusive breastfeeding commitment that breastfeeding requires, for the first 6 months postpartum and the use and the number of factors that mothers of as a supplementary form of take into account when making this com- feeding for up to 2 years in order to confer plex decision, it is important for mothers to

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have good information about what breast- options women have in navigating the feeding can and cannot offer them in return. minefields associated with choosing an infant This chapter presents the state of the feeding method. evidence concerning the advantages and disadvantages of breastfeeding for mothers.1 Questions addressed include: Does breast- THE BIOLOGY OF feeding really help mothers bond with their BREASTFEEDING infants? Are there health benefits of breast- feeding for mothers? Will breastfeeding Background on the biology of breastfeeding change the appearance of the breasts? We is important for understanding how breast- use the term breastfeeding to refer to any feeding can have a widespread impact on amount of breastfeeding, whether it is the maternal psychology and health. Here, we infant’s sole nutritional source or only a present a brief overview. For a more detailed supplemental form of feeding. We use exclu- account of the biological underpinnings of sive breastfeeding, by contrast, to refer to when breastfeeding, see Riordan (2005). infants are only given breast milk and are not The two most important given any other liquid, solid, or vitamins associated with are oxytocin and (Labbok and Krasovec, 1990). This chapter prolactin (see Riordan, 2005). Oxytocin, starts with an overview of the biology of named after the Greek word for “speedy breastfeeding, which forms the basis of many birth,” acts in the body as a smooth muscle of the consequences of breastfeeding contractor, facilitating contractions during discussed. labor and the release of milk during lacta- The core of the chapter summarizes the tion. Prolactin is the primary evidence suggesting that breastfeeding aids responsible for milk production. Prolactin mothers in weight loss and reduces their risk levels increase slowly during pregnancy, for ovarian and breast cancers, along with a triggering changes in the breast tissue that discussion of the influence of breastfeeding stimulate milk production. Oxytocin also on maternal stress, postpartum depression, increases during pregnancy, although more and maternal bonding. We approach many rapidly, quadrupling in volume to stimulate of these topics using the lenses of anthropol- labor (Riordan, 2005). Before a breastfeed- ogy and comparative research, highlighting ing session begins, the mother’s body releases the ways that breastfeeding mothers are oxytocin into the blood stream to aid in milk sometimes very similar and sometimes ejection (White-Traut et al., 2009). Mothers very different from their mammalian coun- separated from their infants before a feeding terparts. The chapter also presents informa- session do not show this prefeeding oxytocin tion on the physical, economic, and social release; therefore, it appears that infant cues costs associated with breastfeeding for moth- drive this effect (McNeilly, Robinson, ers. Finally, we conclude by discussing Houston, & Howie, 1983). During the feed- ing session, when tactile stimulation is received from the , oxytocin and 1 The majority of studies on the impacts of breastfeed- ing have been conducted in the United States; for this prolactin are released in pulsating patterns, reason, studies discussed in this review were U.S.- controlled by nerve fibers linked to the based unless otherwise noted. hypothalamus (Gimpl & Fahrenholz, C17 10/25/2012 15:39:45 Page 416

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2001). Prolactin levels are generally height- mood than do mothers who do not breast- ened in women who are breastfeeding as feed, perhaps aiding in the transition to compared to women who are not breast- motherhood. feeding, although prolactin levels are pro- portionate to breastfeeding frequency and the infant’s milk demands (Battin, Marrs, PHYSICAL HEALTH BENEFITS Fleiss, & Mishell, 1985). OF BREASTFEEDING and are also sup- pressed during lactation, resulting in a period A large research literature suggests that of postpartum infertility, called lactational women who breastfeed experience an array amenorrhea. This natural form of birth con- of health benefits (Bernier, Plu-Bureau, trol remains 98% effective throughout the Bossard, Ayzac, & Thalabard, 2000; Rea, first 6 months of exclusive breastfeeding, as 2004). In the short term, breastfeeding helps long as breast milk is given to the child from mothers lose weight gained during preg- the breast at least every 4 hours during the nancy (Garza & Rasmussen, 2000; Kramer day and every 6 hours during the night & Kakuma, 2004) and helps the uterus (Peterson et al., 2000; Valdes, Labbok, Pugin, contract after pregnancy (Negishi et al., & Perez, 2000). Lactational amenorrhea 1999). Over the long term, breastfeeding becomes a less effective form of contracep- is associated with reduced risk of reproduc- tion (94.6%) if mothers use a breast pump or tive cancers (Bernier et al., 2000), metabolic are separated from their infant for long peri- syndrome (Ford, Giles, & Dietz, 2002; ods (Valdes et al., 2000). This amenorrheic Kramer & Kakuma, 2004), type 2 diabetes state has been observed to last years in (Stuebe & Rich-Edwards, 2009), and malnourished populations seemingly because cardiovascular disease (Schwarz et al., of elevated levels of prolactin (Lunn, Austin, 2009). The literature linking breastfeeding Prentice, & Whitehead, 1984). to improved health has been reviewed else- Until recently, scientists thought that where (Bernier et al., 2000; Rea, 2004). the functions of oxytocin and prolactin Here, we provide a general overview. were limited to birth and lactation, but they now recognize the impact these hor- Weight Loss and Metabolic Syndrome mones have on psychological states. Oxyto- cin and prolactin circulate in the brain and Breastfeeding is calorically costly and is act on their own receptors distributed widely therefore associated with weight loss after across different brain regions (Freeman, pregnancy. Human mothers devote an esti- Kanyicska, Lerant, & Nagy, 2000; Gimpl mated 525 to 625 calories per day producing & Fahrenholz, 2001). Animal research has the 750 mL of milk infants require daily over implicated oxytocin and prolactin in critical the first year of life (Garza & Ramussen, maternal behaviors such as grooming, pro- 2000). A caloric shortfall is experienced in tection, and sensitivity to infant cues most breastfeeding women, who often do (Freeman et al., 2000; Gimpl & Fahrenholz, not report more hunger than nonbreastfeed- 2001). As we discuss later, studies in humans ing women (Heck & de Castro, 1993). have revealed that breastfeeding mothers In a study that followed more than experience lower levels of stress and negative 20,000 Danish women from pregnancy to C17 10/25/2012 15:39:45 Page 417

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18 months postpartum, women who exclu- According to the hypothesis, the reset pro- sively breastfed for the recommended cess causes long-term positive impacts 6 months after birth lost an additional on women’s health, reducing the risk for 2 kgs (4.4 pounds) of pregnancy-related metabolic syndrome, and, consequently, weight by 6 months postpartum than reducing the risk of type 2 diabetes and women who breastfed for shorter durations cardiovascular disease. (Baker et al., 2008). In line with this result, a New research indicates that breastfeed- systematic review of 20 studies showed that ing may reduce the risk of developing both exclusive feeding with breast milk for the type 2 diabetes and cardiovascular disease. first 6 months postpartum predicts signifi- For example, Schwarz and colleagues (2009) cantly greater postpregnancy weight loss found that among 139,681 postmenopausal than with mixed forms of breastfeeding women, those who reported a lifetime his- (breastfeeding while introducing other foods tory of breastfeeding of more than 1 year or liquids) (Kramer & Kakuma, 2004). were less likely to develop postmenopausal Studies have also shown that women diabetes, hypertension, and cardiovascular with a history of breastfeeding have a disease than women who never breastfed. reduced risk of developing metabolic syn- Likewise, another large study found that drome, a combination of medical disorders, women who breastfed over their lifetime such as obesity, insulin resistance, and high for 2 years or more were 23% less likely to blood pressure, which increases the risk of develop coronary heart disease than women cardiovascular disease and diabetes (Ford et who never breastfed, even after controlling al., 2002). A cross-sectional analysis of 2,516 for parental history, early adult adiposity, and midlife women found a 20% reduction in various lifestyle factors (Stuebe et al., 2009). the risk of developing metabolic syndrome Interestingly, some evidence suggests that for every additional year of breastfeeding longer durations of breastfeeding the same women reported (Ram et al., 2008). The child, rather than total time spent breastfeed- authors noted that, although weight loss ing over one’s lifetime, has the greatest pro- associated with breastfeeding accounted for tective benefit against coronary heart disease a significant portion of the reduced risk in (Stuebe, Rich-Edwards, Willett, Manson, & their sample, breastfeeding was associated Michels, 2005). with reductions in metabolic syndrome A study that investigated the relationship risk above and beyond weight loss, even between type 2 diabetes and breastfeeding in when health behaviors and sociodemo- two cohorts of more than 70,000 women graphic variables were statistically con- found that, although the total lifetime dura- trolled. These additional benefits could tion of breastfeeding was associated with owe to the observation that breastfeeding reduced risk of type 2 diabetes, it was longer primes the body to become more metaboli- durations of breastfeeding involving the cally efficient. This idea, dubbed the “reset same child, as opposed to the combined hypothesis,” proposes that breastfeeding duration of breastfeeding across multiple reverses gestational increases in fat accumu- children, that conferred the greatest protec- lation, insulin resistance, and lipid and tive benefits (Stuebe et al., 2005). In this tryglicerin levels more quickly and com- sample, a year of continuously breastfeeding pletely (Stuebe & Rich-Edwards, 2009). one child was associated with a 44% decrease C17 10/25/2012 15:39:45 Page 418

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in risk of developing later diabetes, while a approximately 80% (King, Marks, & year of breastfeeding spread across two chil- Mandell, 2003). In this study, 685 carriers dren was only associated with a 24% ofBRCA1and280carriersofBRCA2 decrease. Whether this finding can be attrib- were compared to 965 women with no uted to the reset hypothesis is unclear, history of ovarian or breast cancer. They although it seems possible that women’s found that cumulative breastfeeding for bodies could require more than half a year longer than a year reduced the risk of of breastfeeding after any given pregnancy to hereditary breast cancer in women with completely reset metabolic action. the BRCA1 mutation, but not the BRCA2 mutation. By contrast, neither Lee et al. (2008) nor Andrieu et al. (2006) observed Breast and Ovarian Cancer an association between breastfeeding and Breastfeeding may also protect against breast breast-cancer risk in women with BRCA1 and ovarian cancers by suppressing ovula- or BRCA2. tion, and thus limiting lifetime estrogen Studies suggest that the risk of ovarian exposure (Clemons & Goss, 2001; Key & cancer is reduced by breastfeeding behaviors Pike, 1988). Theoretically, reductions in as well. A review by Shoham (1994) revealed total estrogen exposure may reduce the that 6 of 11 studies found that breastfeeding risk of breast cancer, because estrogen was related to reduced risk of ovarian cancer. increases rates of breast cell proliferation More recently, researchers analyzed 391 and differentiation, giving more opportuni- cases of epithelial ovarian cancer among ties for mutations to occur and, when they 149,693 women in the Nurses’ Health Study do, fueling cancer growth (Clemons & Goss, (Danforth et al., 2007). They found that for 2001; Key & Pike, 1988). In support of this each month of additional breastfeeding, the model, a meta-analysis of 23 case-control risk of epithelial ovarian cancer was reduced studies found a small protective effect of by 2%. Another study documented a similar breastfeeding on breast cancer: Any lifetime 1.4% reduction in ovarian cancer risk for history of breastfeeding, regardless of dura- every additional month of breastfeeding tion, yielded a benefit, although this effect (Jordan, Siskind, Green, Whiteman, & was small compared to other known biolog- Webb, 2010), although the reduction in ical risk factors (Bernier et al., 2000). This risk did not continue to accrue beyond effect was strongest in nonmenopausal the first 12 months. Breastfeeding has women and in women who had breastfed been found not only to reduce the risk of for longer than 12 months. developing ovarian cancer, but also to Recent research has also begun to improve the chances of surviving in women examine the impact of breastfeeding on who do develop it. One study found that women with hereditary predispositions to women diagnosed with ovarian cancer lived develop breast cancers, with mixed results. longer if they had ever breastfed than if they Jernstrom€ and colleagues (2004), for exam- had never breastfed (Nagle, Bain, Green, & ple, evaluated the role of breastfeeding in Webb, 2008). In this same study, there was women who carried the genetic mutations no relationship between duration or fre- BRCA1 or BRCA2, which are known to quency of breastfeeding and improved ovar- raise the lifetime risk of breast cancer by ian cancer outcomes. C17 10/25/2012 15:39:45 Page 419

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Evidence continues to accumulate dem- brings, it is perhaps unsurprising that approx- onstrating an association between breast- imately one in five women self-report depres- feeding and reduced risk of ovarian and sive symptoms within the first year after birth breast cancers, diabetes, and cardiovascular (Gavin et al., 2005). However, nature may disease. Breastfeeding is a biologically com- also have provided mothers with a stress- plex phenomenon, involving changes in hor- buffer: breastfeeding (Carter & Altemus, mone levels that act on receptors throughout 1997; Groer, Davis, & Hemphill, 2002). the brain and the body. Although the links to Only recently have scientists begun to maternal health are not yet fully known, these recognize the ways that lactation alters a hormone dynamics may exert long-term mother’s stress responses (Groer et al., impacts on women’s health. Reductions in 2002; Lonstein, 2007; Mezzacappa, 2004). diseases related to metabolic syndrome The earliest studies done on rodents revealed may owe, in part, to weight loss and that lactating dams were remarkably resistant improved metabolic function associated to stress. Lactating rodents exposed to stress- with breastfeeding. Breastfeeding also reduces ors, such as electric shocks, fierce predators, lifetime estrogen exposure, potentially or complex mazes, displayed fewer hormo- accounting for reduced risk of reproductive nal and cardiovascular signs of anxiety than cancers among women with a history breast- their nonlactating female counterparts (see feeding. Some studies find dose-response Neumann, 2001, for a review). relationships between increased total dura- Corresponding research in humans has tion of lifetime breastfeeding and better shown a similar association between breast- health outcomes. feeding and reduced stress. The first study conducted in humans showed that breast- feeding women had significantly lower hor- MENTAL HEALTH BENEFITS monal stress responses (as evidence by lower OF BREASTFEEDING cortisol and ACTH) during exercise stress than nonbreastfeeding mothers or women without children (Altemus, Deuster, Gal- Stress Regulation liven, Carter, & Gold, 1995). Several fol- Being a new parent is as stressful as it is low-up studies have since examined rewarding. Sources of maternal stressors women’s cardiovascular and hormonal stress range from worries about being a “good” responses to the classic Treir Social Stress mother (Mercer, 1986) to physical stressors, Task, which involves giving a public speech such as sleep deprivation, body changes, and and doing difficult mental arithmetic in front sexual dysfunction (Gjerdingen, Froberg, of a critical audience. Although these studies Chaloner, & McGovern, 1993). New moth- tend not to find evidence of lower stress ers struggle to find time for their baby while reactivity using hormonal markers of stress, trying to meet the needs of partners, other such as cortisol, they consistently find that children, and themselves (Gruis, 1977). The breastfeeding women have lower cardiovas- vigilance required to be a good parent is also cular markers of stress than do formula- a stressor for new mothers (Hahn-Holbrook, feeding women. Holbrook, & Haselton, 2011). Given all the For example, one study detected lower stressful demands and challenges parenthood cardiovascular markers of stress (as evidence C17 10/25/2012 15:39:45 Page 420

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by lower basal systolic blood pressures, the stress buffering effects of breastfeeding higher levels of cardiac parasympathetic con- appeared to fade as children grew older. trol, and modulation of heart rate reactivity) Breastfeeding mothers with very young during the task in breastfeeders compared infants derived greater stress-buffering with nonbreastfeeding mothers and women from breastfeeding than women who had without children (Altemus et al., 2001). 1-year-old children. Another study found similar cardiovascular Preliminary research suggests links patterns for breastfeeding mothers during between breastfeeding and reduced stress the anticipation of the public-speaking in women’s daily lives outside of the labora- stressor (Light et al., 2000). It is possible tory. Breastfeeding mothers are more likely that any stress-buffering effects of breastfeed- to report positive mood states, less anxiety, ing are more potent directly after the act. and increased calm as compared to formula- Mothers randomly assigned to breastfeed feeding mothers (Altshuler, Hendrick, & before this public-speaking stressor have Cohen, 2000; Carter & Altemus, 1997; blunted cortisol responses when compared Fleming, Ruble, Flett, & Van Wagner, to breastfeeding women who were 1990; Ford et al., 2002; Heinrichs et al., instructed to hold their infants (Heinrichs 2001). These differences between breast- et al., 2001). feeding and formula-feeding mothers The stress-reducing effects of breast- remain after controls for possible confounds, feeding may extend to other stressors as including maternal age, work status, income, well. Mezzacappa, Kelsey, and Katkin and health behaviors (Mezzacappa, Gueth- (2005), for example, compared the cardio- lein, & Katkin, 2002; Mezzacappa, Gueth- vascular responses to difficult mental arith- lein, Vaz, & Bagiella, 2000; Mezzacappa & metic (verbal serial subtractions) and Katlin, 2002). immersion of one’s hand into ice water in While studies in rodents indicate that four groups of women—those exclusively the stress reduction associated with lactation breastfeeding, exclusively formula-feeding, is mediated by the hormones oxytocin mixed feeding (breast and formula), and (Neumann, Torner, & Wigger, 2000; women without children. In response to Windle, Shanks, Lightman, & Ingram, the challenging mental arithmetic, mothers 1997) and prolactin (Bole-Feysot, Goffin, who breastfed exclusively displayed attenu- Edery, Binart, & Kelly, 1998; Freeman ated heart-rate reactivity and shortened pre- et al., 2000), data in humans are more ejection period (PEP; an indicator of the limited. We do know that women with reduced cardiac stress related to the sympa- higher plasma oxytocin and prolactin in thetic nervous system) compared to all other the early postpartum period report less anxi- groups. Moreover, this study found a dose- ety than do women with lower levels of response relationship between breastfeeding these hormones (Nissen, Gustavsson, Wid- frequency and stress reduction. Women strom, & Uvnas-Moberg, 1998; Uvnas- who breastfed more times per day had lower Moberg, Widstrom, Werner, Matthiesen, heart rates in reaction to doing the difficult & Winberg, 1990). Furthermore, breast- mental arithmetic and reduced sympathetic feeding women who release more oxytocin reactivity to the cold water task than women during infant suckling have lower levels of who breastfed less frequently. In this study, cortisol than women who release less C17 10/25/2012 15:39:46 Page 421

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oxytocin during infant feedings (Chiodera et is distinct from other postpartum mood dis- al., 1991). In addition, breastfeeding women orders like the common and transient “post- with higher oxytocin show reduced markers partum blues,” which affects 50% to 80% of of stress while preparing for a public-speak- mothers worldwide (Pitt, 1973; Yalom, ing stressor relative to those with lower Lunde, Moos, & Hamburg, 1968), or the oxytocin (Light et al., 2000). very serious, although rare, occurrence of Research in humans and other species postpartum psychosis (Herzog & Detre, has shown that physiological responses to 1976). The effects of postpartum depression stressors are reduced among lactating relative are insidious because they can disrupt to nonlactating females. In studies with parenting behaviors (Field, 2010), resulting human mothers, the stress-buffering effects in long-term negative consequences on the of breastfeeding appear to be stronger in the cognitive, emotional, and behavioral devel- early postpartum period and soon after a opment of children (Grace, Evindar, & feeding session. Cardiovascular measures of Stewart, 2003). Because of the serious nega- stress, which tap into sympathetic and para- tive consequences of this disorder, there has sympathetic nervous system activity, are been much research identifying predictors of more likely to reveal differences in stress postpartum depression. reactivity between breast- and formula- A recent systematic review identified 12 feeding women than hypothalamic-pitui- studies that reported that breastfeeding tary-adrenal (HPA) axis hormones like cor- women had lower rates of postpartum tisol. Breastfeeding mothers also report less depression in comparison to formula-feed- perceived stress in their daily lives than ing women (Dennis & McQueen, 2009). formula-feeding mothers. The stress-buffer- However, there is an important question ing effect of lactation appears to result from that few studies explicitly address: Does the hormones oxytocin and prolactin in less breastfeeding lead to more depression, nonhumans, although direct evidence in or does more depression lead to less breast- humans in lacking. Collectively, nonhuman feeding? The vast majority of research on and human evidence strongly suggests that this topic to date has focused solely on the breastfeeding is an important regulator of ways that depression can lead to less maternal stress in the postpartum period. breastfeeding. It is easy to imagine why depression might interfere with breastfeeding. Symp- Postpartum Depression toms of depression commonly include Although the birth of a child typically con- decreased motivation, increased anxiety, jures images of joy and fulfillment, many and, for new mothers, avoidance of the women experience feelings of hopelessness infant (Beck, 1992). Breastfeeding is an inti- and despair instead. Postpartum depression is mate behavior demanding sustained periods a devastating mental illness affecting approx- of direct mother–infant contact, which imately 13% of women worldwide within many depressed mothers may find difficult. the first 12 weeks after giving birth (O’Hara Formula-feeding then might seem the more & Swain, 1996), and roughly one in five attractive option for depressed mothers, women within the first postpartum year because it can be performed by other care- (Gaynes et al., 2005). Postpartum depression givers. Furthermore, anxiety associated with C17 10/25/2012 15:39:46 Page 422

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depression can interfere with the maternal oxytocin, which has been found in lower milk supply (Riordan, 2005), leading depre- levels in depressed mothers than in nonde- ssed mothers to feel that they have insufficient pressed mothers (Skrundz, Bolten, Nast, milk and need to switch to formula to ensure Hellhammer, & Meinlschmidt, 2011). that their infant receives adequate nutrition. Women currently using both breastfeeding Finally, many antidepressant medications are and formula-feeding methods report lower not recommended for breastfeeding mothers, levels of negative mood if they are randomly because the active ingredients can be trans- assigned to breastfeed their infant in the ferred to the baby through breast milk and laboratory than if they are randomly assigned could have adverse impacts on infant devel- to formula-feed (Mezzacappa & Katlin, opment (Riordan, 2005). It is not surprising, 2002), perhaps from the oxytocin released then, that studies find depressed mother are by breastfeeding. Breastfeeding is also asso- less likely to breastfeed. ciated with reduced stress (Mezzacappa, Depressed mothers commonly report 2004), and because stress is one of the stron- more difficulties with breastfeeding (Edh- gest risk factors in the development of borg, Friberg, Lundh, & Widstrom, 2005; depression (Hammen, 2005), breastfeeding Tamminen, 1988), lower levels of breast- could buffer women against depression. feeding self-efficacy (Dai & Dennis, 2003), Breastfed infants tend to have easier temper- and more failed breastfeeding attempts aments (Jones, McFall, & Diego, 2004) and (Fergerson, Jamieson, & Lindsay, 2002). fewer health problems over the long term One study found that depressive symptoms (Ip et al., 2007), which could also have seven weeks after delivery predicted higher positive downstream consequences for rates of weaning by 24 weeks postpartum maternal mental health. Taken together, (Galler et al., 1999). Similarly, another study these findings suggest that breastfeeding found that women who were depressed at could confer protective benefits against 2 weeks postpartum were more likely to depression. wean before 2 months postpartum than Very few studies have investigated the women who were not depressed at 2 weeks possibility that breastfeeding might be pro- postpartum (Taveras et al., 2003). tective against postpartum depression. Two Researchers have found that women who studies found that never having breastfed experience depression in pregnancy are less versus having breastfed was associated with likely to initiate breastfeeding (Seimyr, subsequent postpartum depression (Chau- Edhborg, Lundh, & Sjogren,€ 2004). These dron et al., 2001; Hannah, Adams, Lee, studies show that decreased breastfeeding Glover, & Sandler, 1992), and one study behavior follows depression during preg- found that discontinuing breastfeeding ver- nancy and in the early postpartum period. sus continuing to breastfeed was also associ- However, the existence of this relationship ated with subsequent depression (Nishioka does not preclude the possibility that breast- et al., 2011). Critically, however, none of feeding may also exert protective effects these studies controlled for baseline levels of against postpartum depressive symptoms. depression during pregnancy, leaving open There are reasons to think that breast- the possibility that women who engaged in feeding could protect mothers against breastfeeding were simply less depressed depression. The act of breastfeeding releases from the outset. C17 10/25/2012 15:39:46 Page 423

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Only one published study was identified bidirectional (depression leading to less that explicitly set out to test the hypothesis breastfeeding and less breastfeeding leading that breastfeeding is protective against the to depression) or simply unidirectional development of postpartum depression (depression leading to less breastfeeding). (Dennis & McQueen, 2007). This study found that women who exclusively Maternal Bonding breastfed at one week postpartum were equivalently likely to become depressed at Conventional wisdom holds that breastfeed- 4 or 8 weeks postpartum as women who ing helps mothers bond with their babies. In exclusively formula-fed (Dennis & fact, one of the most common reasons given McQueen, 2007), suggesting that there is by women for wanting to breastfeed is the no protective benefit of exclusive breast- opportunity to bond with their children feeding at one week against the develop- (Arora et al., 2000). In the scientific literature ment of depressive symptoms at 4 and 8 as well, breastfeeding is often assumed to aid weeks postpartum. Importantly, however, in maternal–infant attachment, without nec- this study may have been limited in its ability essarily giving reference to direct evidence to detect the mental health benefits of (for examples, see Jansen, Weerth, & breastfeeding, because the mothers in the Riksen-Walraven, 2008). Given this, it is sample had only been breastfeeding for a surprising that only a few studies have actu- very short time. Furthermore, the time ally tested this hypothesis in humans, and frame within which depression was assessed even fewer have found significant results. (between 1 and 8 weeks postpartum) may Here, we review the small literature on the have been too narrow to detect the down- impact of breastfeeding on the mother–child stream effects of breastfeeding on depression. bond (for a more in-depth review, see Jansen Breastfeeding is clearly related to post- et al., 2008). Although the mother–infant partum depression; however, the nature of relationship is bidirectional—in that the that relationship remains somewhat unclear. mother can bond with the infant and the On the one hand, much research has shown infant can bond with the mother—our pri- that depression predicts lower rates of breast- mary focus is maternal bonding. Briefly, feeding initiation and shorter durations of however, we found no studies with evi- breastfeeding. These effects likely result dence that breastfed infants are more from the increased problems depressed securely attached to their mothers than for- women encounter while breastfeeding. mula-fed infants (see Jansen et al., 2008, for a On the other hand, very little research has review). Like the data linking lactation and assessed the possibility that breastfeeding stress, most of what we have learned about might also be protective against postpartum breastfeeding and bonding comes from ani- depression. Given the theoretical reasons to mal studies. think that breastfeeding might be protective Lactation is critical for inciting maternal against depression, further research using behaviors in many mammalian species, longitudinal or experimental designs is because it releases the hormones oxytocin clearly needed before conclusions can be and prolactin, which facilitate maternal drawn about whether the relationship behavior (see Kendrick, 2000, for a review). between depression and breastfeeding is For example, female rats will suddenly C17 10/25/2012 15:39:46 Page 424

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display maternal behaviors if oxytocin affectionate touch, and more attachment- (Pedersen, Caldwell, Peterson, Walker, & related thoughts (Feldman, Weller, Mason, 1992) or prolactin (Bridges, DiBiase, Zagoory-Sharon, & Levine, 2007). Also, Loundes, & Doherty, 1985) is injected into mothers who provide high levels of affec- their brains. If a chemical that blocks the tionate touch during a play session with their actions of oxytocin or prolactin is injected children have higher levels of oxytocin after into the brain of a rat shortly after birth, a the encounter than mothers who provide rodent’s mothering behavior is significantly low levels of affectionate touch (Feldman, impaired (Bridges, Rigero, Byrnes, Yang, & Gordon, Schneiderman, Weisman, & Walker, 2001; van Leengoed, Kerker, & Zagoory-Sharon, 2010). Given this evi- Swanson, 1987). In nonhuman primates, dence, one might predict breastfeeding, however, hormonal changes linked to lacta- which gives women extra bursts of oxytocin, tion play a smaller role in the onset of would lead to greater levels of maternal maternal behaviors, with early learning bonding. and social experience making up the differ- Three out of four studies investigating ence (Pedersen, 2004). For example, admin- whether breastfeeding promotes maternal istration of an oxytocin antagonist into the bonding have found supportive evidence brain of a female rhesus monkey reduces (see Martone & Nash, 1988, for the null certain caregiving behaviors, while leaving result). In the largest study on the topic, others fully intact (Boccia, Goursaud, mother–infant interactions were observed Bachevalier, Anderson, & Pedersen, 2007). at 4 and 12 months postpartum in women Years of observations by primatologists also who had either breastfed for at least a week tell us that maternal behaviors routinely (n ¼ 439) versus women who had not initi- emerge in female primates without the ated breastfeeding (n ¼ 94) (Else-Quest, influence of lactation. For example, female Hyde, & Clark, 2003). The researchers primates who do not have offspring of their found that mothers who had breastfed for own often seek out caregiving opportuni- at least 1 week showed higher-quality inter- ties, such as carrying and grooming infants actions with their babies at 12 months, but (Hrdy, 1999). not at 4 months postpartum. In another Breastfeeding is certainly not necessary study of 405 women, mothers who were for parental bonding to occur in humans, as supplying over half of their infant’s diet adoptive mothers, formula-feeding mothers, though breastfeeding at 5 months postpar- and fathers can attest. However, might tum reported that they were more emotion- breastfeeding give mothers, especially if ally bonded to their infant at that time than they are reluctant or are experiencing moth- women who were supplying less than half of ering challenges, extra incentives to care for their infant’s diet through breast milk or their infant? were not breastfeeding at all (Nishioka Recent studies in humans suggest that et al., 2011). oxytocin is important for maternal bonding. Similarly, Britton, Britton, and Gron- For instance, plasma oxytocin levels during waldt (2006) found that mothers who were pregnancy and the postpartum period pre- breastfeeding at 3 months reported that they dict more maternal bonding behaviors, such felt they were more sensitive to their child’s as eye gaze, vocalizations, positive affect, and needs than women who were not currently C17 10/25/2012 15:39:46 Page 425

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breastfeeding. The findings of the previous POTENTIAL MATERNAL COSTS two studies should be interpreted with cau- OF LACTATION tion, however, because maternal behavior was not rated by objective observers. In fact, Breastfeeding has many possible benefits for Britton, Britton, and Gronwaldt (2006) mothers, but it can also clash with other found women who intended to breastfeed goals for women, such as having a full-time in pregnancy also reported higher sensitivity career. Some of the costs associated with toward their infants at 3 months, suggesting breastfeeding are probably overstated, like that women who choose to breastfeed may sagging breasts, whereas others are likely just be more sensitive (or report being more understated, for example, the social stigma sensitive) from the outset. In fact, other associated with breastfeeding in some socie- studies suggest that the quality of the mater- ties. Breastfeeding can also be problematic nal–infant bond predicts a mother’s willing- for women with certain physical or health ness to breastfeed. A study found that better conditions. Furthermore, many women find bonding behavior 48 hours after birth pre- breastfeeding very difficult because of work dicted higher rates of exclusive breastfeeding constraints or physical pain. Here, we review at 6 months in a sample of more than 500 the potential physical, economic, and social women (Cernadas, Noceda, Barrera, Marti- costs associated with breastfeeding for nez, & Garsd, 2003). mothers. At this early stage of the research, it is too soon to tell whether breastfeeding Physical Costs increases bonding between mothers and infants as compared to other forms of feed- Breastfeeding does have some physical costs ing. This topic deserves additional research for women. Most mothers will have some attention with prospective or experimental nipple discomfort during the first 10 days of designs and objective measures of bonding, breastfeeding (Riordan, 2005). If pain is especially given that many women worry prolonged, a medical assessment by a lacta- that not breastfeeding will interfere with tion consultant or nurse is usually required to their ability to bond with their babies. identify the source of the problem. The most One important observation in the largest common causes of severe nipple pain are of the studies noted (Else-Quest et al., nonideal positioning of the infant at the 2003) was that women who had never breast or poor suckling technique on the breastfed at all exhibited maternal sensitivity part of the infant (Morland-Schultz & Hill, well within the normal range defined by 2005). Both of these can usually be identified clinicians. Oxytocin could still facilitate and remedied by a trained lactation consul- maternal bonding for mothers who do not tant or nurse (Riordan, 2005). Severe nipple breastfeed. For example, direct skin-to-skin pain can sometimes be a sign of a more contact with the infant and affectionate serious breastfeeding-related infection. touch likely increases maternal oxytocin Common infections include , a usu- levels (Uvn€as-Moberg, 1998). These alter- ally benign infection that is easily treatable native mechanisms may be partly responsible by increasing breast milk expression and for bonding in mothers of adopted infants, antibiotics, and candidiasis (or thrush), a fathers, and other caretakers. yeast infection transferred from the baby’s C17 10/25/2012 15:39:46 Page 426

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mouth into the nipple that is treatable with mother loses 200 mg of calcium daily (Rea, antifungal medications (Riordan, 2005). 2004); however, calcium absorption Women can reduce their risk for these becomes more efficient during pregnancy and other breastfeeding-related infections and after weaning often resulting in net by employing good positioning and latching calcium gains over the long term (Riordan, techniques, and by massaging their breasts to 2005). However, in women who are mal- facilitate milk flow (Riordan, 2005). nourished or immunologically compro- Beyond the potential for discomfort, mised, the nutrients required for breastfeeding restricts the types of medica- breastfeeding can overwhelm the mother’s tions a mother can take. A Scandinavian body and lead to health problems. For study found that up to 25% of women example, a randomized clinical trial found took some form of medication while they that breastfeeding among HIV-infected were breastfeeding, and uncertainty regard- women increased maternal death by three- ing the drug’s safety was a major reason for fold at a 2-year follow-up as compared to the discontinuation of breastfeeding (Math- formula feeding (Nduati et al., 2001). The eson, Kristensen, & Lunde, 1990). There are investigators postulated that the nutritional often alternative forms of a drug within the demands posed by breastfeeding may be too same drug class (e.g., antibiotics, selective great for HIV-infected women. With the serotonin reuptake inhibitors, oral contra- exception of malnourished women or ceptives) that are safe for breastfeeding women with HIV, the nutritional costs of women. For example, a women who breastfeeding can usually be met by simply requires medication to treat depression but increasing caloric intake of nutrient-rich who also wants to breastfeed could talk to her foods by 200 to 700 calories per day, doctor about taking Paxil (paroxetine) depending on the frequency of breastfeeding instead of Prozac (fluoxetine) or Trilafon (Riordan, 2005). Mothers are often advised (perphenazine) instead of Nardil (phenel- to take a multivitamin with 100 mg of iron, zine), both of which are considered safe for along with a calcium and omega-3 fatty breastfed infants (Riordan, 2005). Mothers acid supplement, to ensure proper nutrition and healthcare professionals can find advice for the mother and breastfed infant about the safety of medications for breast- (Riordan, 2005). feeding mothers online at LactMed (http:// A common reason that women give for toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen? not breastfeeding is the belief that it will LACT), the U.S. National Library of Medi- adversely affect the appearance of the breasts cine’s drugs and breastfeeding database (U.S. (Arora et al., 2000). Fathers also commonly National Library of Medicine, 2001). worry that breastfeeding will have these Nutrients to synthesize breast milk are effects, leading some men to discourage their often mobilized from maternal stores at the partners from breastfeeding (Bar-Yam & mother’s expense (Dewey, 1997). To offset Darby, 1997). These concerns, however, these costs, the body generally has mecha- are not supported by empirical evidence. nisms in place that help the mother rebound For example, a study of 93 women who from the nutritional stores used during were seeking to improve the breastfeeding. For example, by producing shape of their breasts found no significant 600 to 1,000 mL of breast milk per day, a relationship between objective ratings of C17 10/25/2012 15:39:46 Page 427

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breast ptosis (drooping or sagging) and infant drinks milk from a bottle more breastfeeding initiation or duration (Rinker, quickly and formula is digested more slowly; Veneracion, & Walsh, 2008). The notion therefore, feedings can be performed faster that breastfeeding makes breasts sag likely and less frequently. In addition, because stems from the fact that pregnancy does lead feeding responsibilities can be shared by to changes in breast tissue. This same study other caregivers, feeding with formula found that number of pregnancies, along may also give the mother more freedom. with age, body mass index, larger prepreg- The time commitment associated with nancy cup size, and smoking history breastfeeding can place a burden on women were positively related to breast ptosis. Sim- in the workplace. A breastfeeding mother ilarly, a prospective Italian study found that needs to allocate approximately 45 to 75 mothers frequently reported that the size and minutes per workday to express breast milk the shape of their breasts had changed after (Mohler, 2011). In addition, breastfeeding childbirth, but these changes were not dif- women need a private place to express milk, ferent as a function of infant feeding behav- a place to store breast milk, and the ability to iors (Pisacane & Continisio, 2004). take several breaks per day. It is also possible Breastfeeding appears to have some clear that women who need to make these physical costs for mothers, although these are arrangements are perceived as less serious usually transitory, and most can be amelio- about their jobs, or are stigmatized by co- rated by proper breastfeeding techniques and workers who are uncomfortable with breast- nutrition during breastfeeding. With the feeding (Smith, Hawkinson, & Paull, 2011). exception of women with HIV or severely Given the burden that pumping breast milk malnourished women, there is little evi- at work places on women, it is not surprising dence for any long-term physical costs asso- that women who return to work within 12 ciated with breastfeeding. weeks after birth wean sooner than those who do not return to work within 12 weeks (Callen & Pinelli, 2004). Labor and Economic Costs In a cross-cultural comparison, the Breastfeeding can place a burden on wom- United States was found to have the lowest en’s time and freedom from childcare breastfeeding initiation rates compared to responsibilities. A woman providing breast other industrialized nations such as Canada, milk exclusively to her child has to breast- Sweden, and Australia (Callen & Pinelli, feed her child or express milk approximately 2004), a fact that may be related to American 8 to 12 times per day during the first 6 maternity leave policies (Guendelman et al., months of exclusive breastfeeding (U.S. 2009). In the United States, the Family and Department of Health and Human Services’ Medical Leave Act allows mothers only 12 Office on Women’s Health [OWH], 2011). weeks of unpaid maternity leave. Compare Each breastfeeding or expression session this to Sweden, where parents are entitled to takes approximately 15 to 20 minutes, approximately 16 months of paid leave after meaning that women will spend an esti- the birth of a child (Galtry, 2003). As a result mated 2 to 4 hours per day breastfeeding of this, approximately one-third of Ameri- (OWH, 2011). Actual time spent feeding is can women return to work within 3 months lessened by formula-feeding because the of giving birth, as compared to in Sweden, C17 10/25/2012 15:39:46 Page 428

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where only about 5% return to work within et al., 2001), breastfeeding is associated with 3 months (Klerman & Leibowitz, 1999). It reductions in medical costs (Mohler, 2011). should not be surprising that breastfeeding Breastfeeding also does not require environ- initiation is nearly universal in Sweden (97% mental waste from formula production and of mothers), with approximately 40% of packaging. Furthermore, breastfeeding infants still breastfeeding exclusively at 6 women may save some time that would months (Galtry, 2003). The possible link otherwise be spent preparing formula and between breastfeeding rates and maternity sterilizing bottles. leave policies highlights the role of structural Breastfeeding poses significant burdens factors in shaping infant feeding decisions, on women’s time and freedom during the which are normally thought to simply reflect postpartum period. Feeding with formula personal choices. allows mothers more freedom, because Recently, the U.S. government has other caregivers can care for the infant taken steps that might increase rates of more readily. Pumping breast milk for feed- breastfeeding initiation and its duration. In ings when the mother is absent is also not 2010, President Obama signed the Patient feasible for many women who do not have Protection and Affordable Care Act, which access to adequate support. These costs, includes a provision requiring employers to however, may be offset to some extent by provide a place other than the bathroom and the fact that breastfeeding is less expensive reasonable break time for female employees than formula-feeding, and may lead to con- to express breast milk for the first year after a siderable reductions in healthcare costs and child’s birth. Some employers are exempted, time taken from work because of child and however, because they have fewer than 60 maternal illness over the long term. Future employees or because allowing breaks research might address whether women gain would cause an unreasonable burden for equivalent health benefits from breast the business. pumping and breastfeeding, given that this Although breastfeeding does require question has important implications for substantial time commitments for the women who are in the workforce and mother, which may reduce the time availa- need to pump regularly. ble for work, there may be some economic benefits of breastfeeding. The increased cost Social Costs of formula as compared with breastfeeding is between $1,000 and $4,000 per year per Breastfeeding can have some social costs for baby (Mohler, 2011). Additional indirect women. For example, women often feel cost savings include the possibility that there embarrassed about , will be fewer medical bills related to infant although it is legal in 45 states in the United illness and fewer absences from paid work States. A study found that low-income preg- time for doctor visits with sick infants (Moh- nant women in Missouri felt that discreetly ler, 2011). Because there are possible health breastfeeding in one’s home in front of benefits of breastfeeding, such as reduced visitors was acceptable, but that it was less risk of type 2 diabetes in mothers (Stuebe acceptable to breastfeed in public, especially & Rich-Edwards, 2009) or reduced risk of if people were embarrassed by it or if the gastrointestinal infection in infants (Kramer breastfeeding was not discrete (Libbus & C17 10/25/2012 15:39:46 Page 429

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Kolostov, 1994). Similarly, women often implications for breastfeeding rates (see reported feeling “vulnerable” while breast- Kelley, Watt, and Nazoo, 2006, for a feeding in public and expect to receive review). Women who immigrate to the negative attention for it (Sheeshka et al., United States from cultures where breast- 2001). These feelings can lead women to feeding is more common have higher rates remain housebound or restrict their move- of breastfeeding than the U.S. population. ments during exclusive breastfeeding to For example, Black women who immigrate avoid the social stigma of breastfeeding in to the United States from West Indian Coun- public (Sheeshka et al., 2001). ties—where breastfeeding is the norm—are In cultures where breastfeeding is widely more likely to intend to breastfeed exclu- accepted, women often have more freedom sively after birth than are African American to breastfeed in public places. For example, women (Bonuck, Freeman, & Trombley, Dettwyler (1995b) asserts that in places such 2005). Among Puerto Rican women, length as Mali or Nepal, women are able to breast- of residence in the continental United States feed their infants in public freely and with- is inversely associated with breastfeeding ini- out stigmatization. Dettwyler (1995b) argues tiation (Perez-Escamilla et al., 1998), indicat- that the sexualization of the breast in many ing that living in a culture like the United Western cultures accounts for much of the States where breastfeeding is less common taboo surrounding breastfeeding in public, than in Puerto Rico can alter breastfeeding noting that in Mali and Nepal, where breast- practices. feeding in public is completely socially There is also variation across cultures in acceptable, breasts do not have the same beliefs about the appropriate age to wean a sexual connotation for men or women child. Women who violate their local norms that they do elsewhere in the world. In can face social stigma. Although the average cultures where the primary function of the duration of breastfeeding in traditional soci- breast is thought to be sexual, the sight of a eties is approximately 2.5 years (Dettwyler, women breastfeeding is often considered 1995a), many women in the United States “perverted” or “obscene.” For example, report that they receive negative reactions the popular social networking website, Face- from others if they breastfeed past the first book, officially banned pictures of women few months postpartum (Kendall-Tackett & breastfeeding their infants, claiming that these Sugarman, 1995). In a survey conducted in photos violated their decency code by show- the United States, the percentage of mothers ing an exposed breast (Worthman, 2009). citing “social stigma” as a negative aspect of Women who breastfeed in cultures where breastfeeding was strongly related to the age breastfeeding is taboo often face continual of the child: 29% of women breastfeeding pressure from friends and family to use for- past 6 months and 61% of women breast- mula, have low breastfeeding confidence, feel feeding past 24 months reported feeling intense stigma around breastfeeding in public, stigma as a result of breastfeeding and have very little access to breastfeeding (Kendall-Tackett & Sugarman, 1995). information outside of medical professionals Recent research also suggests that (Scott & Mostyn, 2003). breastfeeding women face social stigma in The social acceptability of breastfeeding the United States regardless of where or how varies by culture and ethnicity, which has long they choose to feed their infants. In a C17 10/25/2012 15:39:46 Page 430

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series of studies conducted with college co-parents the benefits of breastfeeding for students, breastfeeding mothers were rated their child, involving co-parents in breast- as less competent and less likely to be hired feeding decisions, and having co-parents for a hypothetical job compared to mothers provide instrumental support (like helping who were not breastfeeding or women with chores or entertaining company) without children (Smith et al., 2011). In (Gamble & Morse, 1993). Additionally, this research, the negative effects of breast- co-parents may participate in infant feeding feeding were comparable, in terms of the directly if breastfeeding mothers use a breast- negative perceptions evoked in the minds of pump to express milk that can be fed to the both male and female students, to a woman’s infant in a bottle. decision to purposefully sexualize her breasts Another factor that can lead partners to (Smith et al., 2011). These results suggest have negative attitudes toward breastfeeding that although breastfeeding may have many is its impact on women’s sexuality (Rempel benefits for the mother, mothers who choose & Rempel, 2011). Breastfeeding lowers to breastfeed may also suffer social costs. women’s estrogen levels in the early post- Moving into the private realm, mothers partum period (Battin et al., 1985), which may also be concerned that breastfeeding can lead to decreases in sexual desire and will have negative consequences for their cause vaginal dryness for a subset of women, social relationships. Breastfeeding is an inti- making sex painful (Brown & McDaniel, mate experience between a mother and her 2008). For example, breastfeeding women child that can sometimes lead the other report more vaginal pain during intercourse parent to feel left out. Fathers sometimes at 3 months postpartum than formula-feed- report that breastfeeding interrupts their ing women, although there was no differ- ability to form a relationship with the new ence at 6 months postpartum (Connolly, infant (Bar-Yam & Darby, 1997). Even Thorp, & Pahel, 2005). Another study found when fathers are supportive of their partners’ that breastfeeding at 3 months (but not 6 breastfeeding, many also admit to feelings of months) was related to reduced frequency of jealousy at their inability to contribute dur- sex, sexual desire, and sexual satisfaction as ing the feeding process (Rempel & Rempel, compared to women who were not breast- 2011). In-depth interviews with fathers sug- feeding (Judicibus & McCabe, 2002). Over- gest that these feelings can lead fathers to all, women perceive that breastfeeding has a postpone the forming of a relationship with slightly negative impact on the physiological the child until after the infant is weaned or to aspects of sexuality; however, most report compensate by becoming more involved in that it does not greatly affect the sexual other aspects of caring for the infant (i.e., relationship with their partner (Avery, baths, diapers) (Gamble & Morse, 1993). Duckett, & Frantzich, 2000). In one study, Presumably, the feeling of being left out the majority of women (60.3%) perceived of the parenting process can also extend to that the baby’s father thought breastfeeding families in which two women co-parent, but made them neither more nor less sexually only one breastfeeds the baby. desirable than before pregnancy, while Families can sometimes alleviate these 12.7% thought it made them less sexually negative feelings in co-parents by framing attractive, and 27% thought it made them breastfeeding as a team effort, discussing with more attractive to their partner. C17 10/25/2012 15:39:47 Page 431

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Although there are social costs associated but that pressuring them or creating guilt for with breastfeeding for mothers, there can lack of success is not (Dillaway & Douma, also be social costs associated with not breast- 2004). Nonetheless, even when healthcare feeding (Hauck & Irurita, 2003). Because of professionals are sensitive in their approach, the widespread beliefs about the positive family, friends, and even strangers share their effects of breastfeeding on a child, women advice about best practices for breastfeeding sometimes feel extensive social pressure to initiation, duration, and weaning. Interviews breastfeed. Although most mothers (approx- with new mothers have revealed that when imately 96%; Simopoulos & Grave, 1984) the expectations of others do not match the are physically capable of breastfeeding, other choices of the mother, mothers can often barriers—just as real—can make breastfeed- feel guilt (Hauck & Irurita, 2003). ing nearly impossible. If women do not have Breastfeeding is associated with some access to accurate information regarding social costs. Mothers can become socially proper breastfeeding techniques, they may restricted by breastfeeding because they do not produce enough milk to support the not feel comfortable breastfeeding in public needs of their infant or may develop physical places. Furthermore, breastfeeding mothers problems that make breastfeeding painful. are stigmatized and perceived as less compe- Furthermore, many mothers must work to tent than nonbreastfeeding mothers, a fact financially support the needs of their chil- that could have negative consequences for dren and are not allowed convenient or women in the workplace or for women who flexible breaks to breast pump, nor are breastfeed for periods beyond the cultural they given the space necessary to pump norm. Finally, some women find that breast- and store their breast milk. feeding reduces their sex drive for a time or Whatever the reasons behind the deci- makes their partners feel left out of the sion not to breastfeed, many women feel childcare experience. There are, however, that this decision will lead to the perception also social costs associated with not breast- that they are “bad mothers” (Ladd-Taylor & feeding, such as being branded a “bad Umansky, 1998). As one mother recounts, mother” or being made to feel guilty. “I was feeling very guilty [for stopping breastfeeding] and I didn’t know what to do” (Hauck & Irurita, 2003, p. 70). There CONCLUSIONS have even been select reports of medical professionals pushing the “breast is best” This chapter reviewed the scientific research message, regardless of the mother’s circum- on the benefits and costs associated with stances and choices, leading some mothers to breastfeeding for mothers. Many studies report they are breastfeeding “just to keep point out that breastfeeding is associated the nurses happy” (Bauer, 2000, p. 15). with many health benefits for mothers, These overt instances of pressure from health including reduced risk for metabolic syn- professionals are likely extreme, rare exam- drome and certain reproductive cancers. ples. For many years, physicians, breastfeed- Furthermore, evidence suggests that breast- ing consultants, nurses, and clinical experts feeding could buffer women against biolog- have been aware that encouraging mothers ical and psychosocial stressors during the to breastfeed by supporting them is helpful, postpartum period. Little evidence is C17 10/25/2012 15:39:47 Page 432

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available examining whether breastfeeding Control and Prevention, 2011b). However, reduces the risk of postpartum depression policy makers and medical professionals or increases maternal bonding to the infant. should also realize that variation in mothers’ More research is needed in each of these areas. circumstances—both personal and struc- Although research has often focused on tural—affect whether breastfeeding is the the benefits of breastfeeding for mothers, best choice for a particular woman and there is also evidence of substantial costs her child. associated with breastfeeding. Mothers must devote several hours per day to breast- feeding if it is the sole feeding method, and REFERENCES some mothers feel confined to their homes because they are uncomfortable breastfeed- Altemus, M., Deuster, P. A., Galliven, E., Carter, C. ing in public. Breastfeeding mothers also S., & Gold, P. W. (1995). Suppression of hypo- face significant logistical and professional thalmic-pituitary-adrenal axis responses to stress challenges in the workplace. Finally, the in lactating women. Journal of Clinical Endocrinol- – majority of women will experience some ogy & Metabolism, 80(10), 2954 2959. doi: 10.1210/jc.80.10.2954 discomfort during breastfeeding, particularly Altemus, M., Redwine, L. S., Leong, Y. M., Frye, C. early in the postpartum period, which can A., Porges, S. W., & Carter, C. S. (2001). sometimes develop into painful conditions Responses to laboratory psychosocial stress in requiring medical attention. postpartum women. Psychosomatic Medicine, 63 More studies are needed to evaluate (5), 814–821. these many trade-offs in the benefits and Altshuler, L. L., Hendrick, V., & Cohen, L. S. (2000). costs of breastfeeding at both the population An update on mood and anxiety disorders during pregnancy and the postpartum period. Primary and individual level. Even if studies demon- Care Companion Journal of Clinical Psychiatry, 2(6), strate that the benefits of breastfeeding out- 217–222. weigh the costs for women as a group, Andrieu, N., Goldgar, D. E., Easton, D. F., Rookus, decisions for individual mothers need to M., Brohet, R., Antoniou, A. C., . . . Chang- be made based on their personal circum- Claude, J. (2006). Pregnancies, breast-feeding, and breast cancer risk in the International stances, which will vary in the many com- BRCA1/2 Carrier Cohort Study (IBCCS). Jour- plex and multifaceted trade-offs described in nal of the National Cancer Institute, 98(8), 535–544. this chapter. Because of the growing evi- doi: 10.1093/jnci/djj132 dence of the health benefits of breastfeeding Arora, S., McJunkin, C., Wehrer, J., & Kuhn, P. for infants and their mothers, it makes sense (2000). Major factors influencing breastfeeding ’ ’ for social policies to attempt to reduce bar- rates: Mother s perception of father s attitude and milk supply. Pediatrics, 106(5), E67. riers to breastfeeding. Policy makers and Avery, M. D., Duckett, L., & Frantzich, C. R. (2000). healthcare professionals have made strides The experience of sexuality during breastfeeding in breastfeeding promotion in recent years among primiparous women. The Journal of (Centers for Disease Control and Preven- Midwifery & Women’s Health, 45(3), 227–237. tion, 2011b). Educating mothers, partners, doi: 10.1016/s1526-9523(00)00020-9 families, and communities about the health Baker, J. L., Gamborg, M., Heitmann, B. L., Lissner, fi L., Sorensen, T. I., & Rasmussen, K. M. (2008). bene ts of breastfeeding, along with how to Breastfeeding reduces postpartum weight reten- overcome the challenges, have proven to be tion. American Journal of Clinical Nutrition, 88(6), particularly effective (Centers for Disease 1543–1551. doi: 10.3945/ajcn.2008.26379 C17 10/25/2012 15:39:47 Page 433

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