The Reset Hypothesis: Lactation and Maternal Metabolism

For maternal metabolism, pregnancy ends not with delivery, but with weaning. In several recent epidemiological studies, authors have reported an association between duration of breast-feeding and reduced maternal risk of metabolic disease. These findings parallel data from animal models showing favorable changes in metabolism associated with lactation. During gestation, visceral fat accumulates, and insulin resistance and lipid and triglyceride levels increase. These changes appear to reverse more quickly, and more completely, with lactation. In this article, we review animal and human studies regarding the effects of lactation on adiposity, lipid, and glucose homeostasis. We hypothesize that lactation plays an important role in “resetting” maternal metabolism after pregnancy

Inflammation and weight gain in reproductive-aged women

To investigate whether mid-pregnancy inflammation predicts rate of subsequent gestational weight gain (GWG), and whether inflammation at 3 years postpartum is associated with weight and waist circumference (WC) gain during a median of 4.4 years follow-up

Gestational weight gain and child adiposity at age 3 years

OBJECTIVE The purpose of this study was to examine the associations of gestational weight gain with child adiposity. STUDY DESIGN Using multivariable regression, we studied associations of total gestational weight gain and weight gain according to 1990 Institute of Medicine guidelines with child outcomes among 1044 mother-child pairs in Project Viva. RESULTS Greater weight gain was associated with higher child body mass index z-score (0.13 units per 5 kg [95% CI, 0.08, 0.19]), sum of subscapular and triceps skinfold thicknesses (0.26 mm [95% CI, 0.02, 0.51]), and systolic blood pressure (0.60 mm Hg [95% CI, 0.06, 1.13]). Compared with inadequate weight gain (0.17 units [95% CI, 0.01, 0.33]), women with adequate or excessive weight gain had children with higher body mass index z-scores (0.47 [95% CI, 0.37, 0.57] and 0.52 [95% CI, 0.44, 0.61], respectively) and risk of overweight (odds ratios, 3.77 [95% CI: 1.38, 10.27] and 4.35 [95% CI: 1.69, 11.24]). CONCLUSION New recommendations for gestational weight gain may be required in this era of epidemic obesity

Maternal Depressive Symptoms Not Associated with Reduced Height in Young Children in a US Prospective Cohort Study

Background: Shorter stature is associated with greater all cause and heart disease mortality, but taller stature with increased risk of cancer mortality. Though childhood environment is important in determining height, limited data address how maternal depression affects linear growth in children. We examined the relationships between antenatal and postpartum depressive symptoms and child height and linear growth from birth to age 3 years in a U.S. sample. Methods: Subjects were 872 mother-child pairs in Project Viva, a prospective pre-birth cohort study. The study population is relatively advantaged with high levels of income and education and low risk of food insecurity. We assessed maternal depression at mid-pregnancy (mean 28 weeks' gestation) and 6 months postpartum with the Edinburgh Postnatal Depression Scale (score > = 13 on 0–30 scale indicating probable depression). Child outcomes at age 3 were height-for-age z-score (HAZ) and leg length. HAZ was also available at birth and ages 6 months, 1, 2, and 3 years. Findings: Seventy (8.0%) women experienced antenatal depression and 64 (7.3%) experienced postpartum depression. The mean (SD) height for children age 3 was 97.2 cm (4.2), with leg length of 41.6 cm (2.6). In multivariable linear regression models, exposure to postpartum depression was associated with greater HAZ (0.37 [95% confidence interval: 0.16, 0.58]) and longer leg length (0.88 cm [0.35, 1.41]). The relationship between postpartum depression and greater HAZ was evident starting at 6 months and continued to age 3. We found minimal relationships between antenatal depression and child height outcomes. Conclusion: Our findings do not support the hypothesis that maternal depression is associated with reduced height in children in this relatively advantaged sample in a high-income country

Maternal age and other predictors of newborn blood pressure

Objective To investigate perinatal predictors of newborn blood pressure. Study design Among 1059 mothers and their newborn infants participating in Project Viva, a US cohort study of pregnant women and their offspring, we obtained five systolic blood pressure readings on a single occasion in the first few days of life. Using multivariate linear regression models, we examined the extent to which maternal age and other pre- and perinatal factors predicted newborn blood pressure level. Results Mean (SD) maternal age was 32.0 (5.2) years, and mean (SD) newborn systolic blood pressure was 72.6 (9.0) mm Hg. A multivariate model showed that for each 5-year increase in maternal age, newborn systolic blood pressure was 0.8 mm Hg higher (95% CI, 0.2, 1.4). In addition to maternal age, independent predictors of newborn blood pressure included maternal third trimester blood pressure (0.9 mm Hg [95% CI, 0.2, 1.6] for each increment in maternal blood pressure); infant age at which we measured blood pressure (2.4 mm Hg [95% CI 1.7, 3.0] for each additional day of life); and birth weight (2.9 mm Hg [95% CI, 1.6, 4.2] per kg). Conclusions Higher maternal age, maternal blood pressure, and birth weight were associated with higher newborn systolic blood pressure. Whereas blood pressure later in childhood predicts adult hypertension and its consequences, newborn blood pressure may represent different phenomena, such as pre- and perinatal influences on cardiac structure and function. Development of risk for adult cardiovascular disease begins very early in life, even before birth.1 Data are scarce, however, regarding blood pressure in the newborn period, which may reflect pre- and perinatal influences on cardiac structure and function. The few studies that have examined determinants of newborn blood pressure suggest a direct association with birth weight,2.; 3.; 4.; 5.; 6.; 7.; 8.; 9. ; 10. in contrast to the inverse association seen with older infants, children, and adults.11 However, most of these studies have at least one important limitation, such as a relatively small sample size of term newborns, lack of data on potentially confounding variables, and limited data on maternal predictors. Maternal age is of particular interest given the known associations of advanced age with adverse reproductive outcomes, including reduced fertility, preterm birth, impaired fetal growth, multiple birth, and congenital anomalies.12.; 13. ; 14. The additional associations of advanced maternal age with diabetes and hypertension,15. ; 16. with possible diminished uterine vascular and placental function,17. ; 18. and in at least two reports with blood pressure level in childhood and in adolescence19. ; 20. warrant examination of its influence on newborn blood pressure. The purpose of this analysis was to investigate associations of pre- and perinatal factors, including maternal age, with systolic blood pressure level during the first few days of life among members of Project Viva, a cohort study of pregnant women and their children

Childhood Abuse and Age at Menarche

Purpose—Physical and sexual abuse are prevalent social hazards. We sought to examine the association between childhood physical and sexual abuse and age at menarche. Methods—Among 68,505 participants enrolled in the Nurses’ Health Study II we investigated the association between childhood physical abuse and sexual abuse on menarche prior to age 11 (early) or after age 15 (late) using multivariate logistic regression analysis, mutually adjusting for both types of abuse. Results—Fifty-seven percent of respondents reported some form of physical or sexual abuse in childhood. We found a positive dose-response association between severity of sexual abuse in childhood and risk for early menarche. Compared to women who reported no childhood sexual abuse, the adjusted odds ratio [AOR] for early menarche was 1.20 (95% confidence interval [CI], 1.10, 1.37) for sexual touching and 1.49 (95% CI, 1.34, 1.66) for forced sexual activity. Only severe physical abuse predicted early menarche (AOR=1.22, 95% CI, 1.10–1.37). Childhood physical abuse had a dose-response association with late age at menarche: AOR 1.17 (95% CI, 1.04, 1.32) for mild, 1.20 (95% CI, 1.08, 1.33) for moderate, and 1.50 (95% CI, 1.27, 1.77) for severe physical abuse. Sexual abuse was not associated with late menarche. Conclusion—Childhood abuse was very prevalent in this large cohort of U.S. women. Severity of childhood sexual abuse was associated with risk for early onset of menarche, and physical abuse was associated with both early and late onset menarche. Implications and Contribution—The severity of childhood sexual abuse and severe physical abuse were associated with risk for accelerated menarche, while severity of childhood physical was associated with risk for delayed onset of menarche. The nature of the association between different forms of childhood adversities and reproductive lifespan may vary

Duration of Lactation and Maternal Adipokines at 3 Years Postpartum

Objective: Lactation has been associated with reduced maternal risk of type 2 diabetes, the metabolic syndrome, and cardiovascular disease. We examined the relationship between breastfeeding duration and maternal adipokines at 3 years postpartum. Research Design and Methods: We used linear regression to relate the duration of lactation to maternal leptin, adiponectin, ghrelin, and peptide YY (PYY) at 3 years postpartum among 570 participants with 3-year postpartum blood samples (178 fasting), prospectively collected lactation history, and no intervening pregnancy in Project Viva, a cohort study of mothers and children. Results: A total of 88% of mothers had initiated breastfeeding, 26% had breastfed $\geq 12$ months, and 42% had exclusively breastfed for $\geq 3$ months. In multivariate analyses, we found that duration of total breastfeeding was directly related to PYY and ghrelin, and exclusive breastfeeding duration was directly related to ghrelin (predicted mean for never exclusively breastfeeding: 790.6 pg/mL vs. $\geq 6$ months of exclusive breastfeeding: 1,008.1 pg/mL; P < 0.01) at 3 years postpartum, adjusting for pregravid BMI, gestational weight gain, family history of diabetes, parity, smoking status, and age. We found a nonlinear pattern of association between exclusive breastfeeding duration and adiponectin in multivariate-adjusted models. Conclusions: In this prospective cohort study, we found a direct relationship between the duration of lactation and both ghrelin and PYY at 3 years postpartum