The caloric demand of lactation does not alter spontaneous meal patterns, nutrient intakes, or moods of women

Childbirth and mental disorders

This review approaches the topic of childbirth and mental illness using a model of perinatal health which takes into consideration the multiple determinants of health, approached from a lifespan perspective. The paper seeks to answer four broad questions using this model and available literature: (1) What is the relationship between childbirth and mental disorders? (2) How common are mental disorders during childbearing, and what is the perinatal course of illness? (3) What are the effects of mental illness during childbearing on foetal and infant developmental outcomes? (4) How do you approach the detection and treatment of mental disorders during the perinatal period?

Newborn right-holding is related to depressive symptoms in bottle-feeding mothers but not in breastfeeding mothers

This study examines the relationships between infant holding preferences and maternal depression according to the newborn feeding mode. Links between depression and infant holding biases have been observed in mothers [Vauclair, J., Scola, C. (in press). Dépression, alexithymie et latéralisation dans la façon de porter un nouveau-né [Infant holding biases in relation to depression, alexithymia and laterality]. Annales Médico-psychologiques; Weatherill, R. P., Almerigi, J. B., Levendosky, A. A., Bogat, G. A., von Eye, A., & Harris, L. J. (2004). Is maternal depression related to side of infant holding? International Journal of Behavioral Development, 28, 421-427] but the fact that breastfeeding has never been studied in relation to these two factors is surprising as breastfeeding has some influence on depression (e.g., [Mezzacappa, E. S., Guethlein, W., Vaz, N., & Bagiella, E. (2000). A preliminary study of breast-feeding and maternal symptomatology. Annals of Behavioral Medicine, 22, 71-79]) and must also affect holding biases. Mothers who just gave birth (N=100) were tested few days after delivery. Measures of handedness, infant holding-side preferences, and level of depressive symptoms expressed by mothers (assessed with the CES-D scale) were collected via questionnaires. Asymmetries in emotional perception were assessed via a Chimeric Figure Task and a Dichotic Listening Task. Results showed that breastfeeding (1) reduced left-side bias for holding newborns and (2) was associated with lowest levels of depressive symptoms. Moreover, holding biases were related to maternal depression in bottle-feeding but not in breastfeeding mothers, namely that holding on the right-side while bottle-feeding was associated with higher levels of depressive symptoms. These results were not due to hemispheric specialization as auditory and visual asymmetries were similar between breastfeeding and bottle-feeding mothers. The discussion emphasizes the striking role of the early mother/child relationship's establishment on infant holding biases.

Regulation of anxiety during the postpartum period

Healthy mother-infant interactions are critical for the physical, cognitive, and psychological development of offspring. Such interactions rely on numerous factors, including a positive maternal emotional state. However, many postpartum women experience emotional dysregulation, often involving elevated anxiety. Neuroendocrine factors contributing to the onset of postpartum anxiety symptoms are mostly unknown, but irregularities in hypothalamic-pituitary-adrenal axis function, reduced prolactin and oxytocin signaling, or parturitional withdrawal of ovarian, placental and neural steroids could contribute to anxiety in susceptible women. Although the causes of initial onset are unclear, postpartum anxiety can be mitigated by recent contact with infants. Numerous neurochemical systems, including oxytocin, prolactin, GABA, and norepinephrine mediate this anxiolytic effect of infant contact. Insight into the etiology of postpartum anxiety disorders, and how contact with infants helps counter existing anxiety dysregulation, will surely facilitate the diagnosis and treatment of postpartum women at risk for, or experiencing, an anxiety disorder.

Deficits in plasma oxytocin responses and increased negative affect, stress, and blood pressure in mothers with cocaine exposure during pregnancy

In animals, oxytocin enhances maternal behavior and lowers blood pressure (BP) and negative affect, while parturitional cocaine disrupts oxytocin activity and increases maternal neglect and aggression. Thus, we compared oxytocin, BP, maternal behavior, and affect in mothers of infants who used cocaine (cocaine, n = 10) or did not (no drug, n = 25) during pregnancy. Laboratory BP and circulating oxytocin, catecholamines, and cortisol were examined before and during a speech stressor on 2 days, with vs. without prestress baby holding. Ambulatory monitoring assessed BP, urinary norepinephrine, and cortisol for 24 h at home. The cocaine group had lower oxytocin levels, greater hostility and depressed mood, less support from others and mastery over life events, higher BP during all events of testing without the baby, and higher ambulatory BP and urinary norepinephrine at home, while cortisol and epinephrine responses were blunted. Although they tended to hold their babies less often at home, baby holding in the laboratory led to decreased BP in cocaine mothers who then did not differ from no-drug mothers in BP or observed affect.

Breastfeeding and Maternal Stress Response and Health

This article reviews findings on the maternal stress and health effects of lactation. Several significant associations have emerged. Compared with not breastfeeding, breastfeeding is associated with increased parasympathetic nervous system modulation, greater vascular stress response, lower perceived stress levels, and fewer depressive symptoms. Breastfeeding exclusively is associated with an attenuated initial sympathetic cardiac nervous system response to some laboratory stressors. Bottle-feeding is associated with increased sympathetic and decreased parasympathetic cardiac control. The act of breastfeeding is associated with decreased neuroendocrine response to stressors and decreased negative mood. Finally, breastfeeding is associated with enhanced physical and mental health compared with non-breastfeeding.

Breast-feeding and maternal health in online mothers

Self-reports of mothers currently breast-feeding (n = 561) and mothers who had breast-fed in the past (n = 452) were compared for perceived stress, self-reports of upper respiratory infection symptoms, and physician visits for psychological illnesses. Possible demographic confounds were controlled statistically. In analyses examining breast-feeding status as a dichotomous variable (current vs. past), breast-feeding was negatively associated with perceived stress and upper respiratory symptoms (the latter association dissolved when controlling for perceived stress), but not with physician visits for psychological illnesses. However, analyses of the continuous variables of frequency of breast-feeding and cumulative amount of breast-feeding revealed negative associations, and analyses of times since last nursing revealed positive associations with likelihood for physician visits for psychological illnesses. Frequency of bottle-feeding was positively associated with perceived stress. The results support the interrelatedness of breast-feeding and maternal health in online mothers.

Neuroendocrine and emotional changes in the post-partum period

As well as having widespread effects on many aspects of mammalian physiology, the hormones of both the reproductive and stress axes can directly and indirectly influence behavior. Here we review possible mechanisms through which centrally active hormones of the female reproductive system and the hypothalamo-pituitary-adrenal stress axis may interact to influence behavior and mood states during the post-partum period. We will focus primarily on the behavioral effects of selected neuropeptide hormones, in particular oxytocin, vasopressin and corticotrophin-releasing hormone. The literature documenting central behavioral effects of these neuropeptides arises almost exclusively from research in experimental animals. In particular, it has been reported that during lactation in rats there are high blood and brain levels of oxytocin. At the same time there is a reduction in corticotrophin-releasing hormone in the brain and in its secretion in response to stress. These changes may contribute to optimal maternal care of the offspring. Correlational studies of peptides and behavior in the post-partum period also support the hypothesis that neuropeptides may influence human physiology and behavior. Studies of post-partum women reveal powerful regulatory effects of lactation on the reactivity of the hypothalamo-pituitary-adrenal axis and of autonomic and immune systems, especially in the face of challenge. The integrative function of neural systems that influence both reproduction and the hypothalamo-pituitary-adrenal axis suggests one central mechanism for mediating the effects of environmental challenges.

Responses to laboratory psychosocial stress in postpartum women

OBJECTIVE

Lactation has been associated with attenuated hormonal responses to exercise stress in humans. This study was designed to determine the effect of lactation on hypothalamic-pituitary-adrenal axis, autonomic nervous system, and anxiety responses to psychological stress.

METHOD

The Trier Social Stress Test was administered to 24 lactating women, 13 postpartum nonlactating women, and 14 healthy control women in the early follicular phase of the menstrual cycle. Lactating women were stressed at least 40 minutes after last feeding their infant.

RESULTS

ACTH, cortisol, heart rate, diastolic blood pressure, systolic blood pressure, and subjective anxiety ratings were all significantly increased in response to the psychological stress (all p <.0001). There were no differences among the three groups in any of these responses to the stress. However, postpartum nonlactating women did have a persistently higher systolic blood pressure and lower cardiac vagal tone than the lactating women and control subjects. In addition, the typical negative correlation between cardiac vagal tone and heart rate was consistently higher in lactating women than nonlactating postpartum women and controls, which suggests stronger vagal control of heart rate in lactating women. In addition, there was no change in oxytocin or allopregnanolone in response to the stress, and baseline oxytocin and allopregnanolone levels did not differ among the three groups.

CONCLUSIONS

These results indicate that physiological and subjective responses to social stress are not attenuated in lactating women tested at least one hour after feeding their infant. However, enhanced vagal control of cardiac reactivity was observed in lactating women. In addition, postpartum women who did not lactate showed evidence of increased sympathetic and decreased parasympathetic nervous system tone.

A preliminary study of breast-feeding and maternal symptomatology

The association between breast-feeding status and maternal health is examined. A survey questionnaire was presented via the World Wide Web. Self-reports of 168 breast-feeding and 65 weaned mothers between 4 and 208 weeks postpartum were compared for physician visits, symptomatology, and Perceived Stress Scale scores in the last month. Breast-feeding was associated with fewer physician visits and symptoms and less perceived stress. Moreover, the longer a woman breast-fed before she weaned, the fewer the symptoms and less stress she reported. Breast-feeding is associated with better maternal health both during the breast-feeding period and after weaning. Further research on the effects on maternal health of breast-feeding is indicated. Future prospective longitudinal investigations should address the possible inhibition of lactation by stress and physiological mechanisms that may link breast-feeding and weaning with maternal health.

Oxytocin responsivity in mothers of infants: a preliminary study of relationships with blood pressure during laboratory stress and normal ambulatory activity

The neuropeptide oxytocin (OT) enhances maternal behavior and decreases blood pressure (BP) and stress responses in animals. Thus, the relationship of OT responsivity to BP in 14 breast- and 11 bottle-feeding mothers of infants was examined. Laboratory BP was assessed during baseline, speech preparation, active speech, and recovery on 2 days, 1 in which baseline and speech were separated by 10 min of baby holding and the other by no baby contact. Systolic BP reactivity to speech was lower after baby contact. Plasma OT change from baseline to speech after baby contact defined OT increase, minimal OT change, and OT decrease groups. OT increase mothers were primarily breast-feeders, and they had lower BP throughout both stress sessions and after baby feeding at home than OT decrease mothers, who also had greater BP reactivity to preparation and recovery. These results suggest that oxytocin has antistress and BP-lowering effects in humans.

Breastfeeding and the use of human milk. American Academy of Pediatrics. Work Group on Breastfeeding

This policy statement on breastfeeding replaces the previous policy statement of the American Academy of Pediatrics, reflecting the considerable advances that have occurred in recent years in the scientific knowledge of the benefits of breastfeeding, in the mechanisms underlying these benefits, and in the practice of breastfeeding. This document summarizes the benefits of breastfeeding to the infant, the mother, and the nation, and sets forth principles to guide the pediatrician and other health care providers in the initiation and maintenance of breastfeeding. The policy statement also delineates the various ways in which pediatricians can promote, protect, and support breastfeeding, not only in their individual practices but also in the hospital, medical school, community, and nation.

A preliminary study of the effects of breast-feeding on maternal health

This study is a preliminary investigation of the effects on breast-feeding and cessation of breast-feeding on maternal health. A self-report questionnaire assessed overall health, mood, stress, and psychological and upper respiratory infection symptoms in 14 current, 36 never, and 49 past breast-feeders. Results indicated that breast-feeding did not incur greater health costs to the mother compared with bottle-feeding and that cessation of breastfeeding was associated with worse mood, more stress, and a greater number of psychological symptoms compared with current breast-feeding. Physiological mechanisms, as opposed to personality factors, are discussed as a basis for these findings.