Gestational Diabetes Mellitus Is Associated with Differences in Human Milk Hormone and Cytokine Concentrations in a Fully Breastfeeding United States Cohort.

It is unclear whether gestational diabetes mellitus (GDM) alters breast milk composition. We prospectively examined associations of GDM status with concentrations of six potentially bioactive elements (glucose, insulin, C-reactive protein (CRP), interleukin-6 (IL-6), leptin, and adiponectin) in human milk. These were measured at both 1 and 3 months postpartum in 189 fully breastfeeding women. Mixed-effects linear regression assessed GDM status-related differences in these milk bioactives, adjusting for demographics, maternal factors, and diet. At 1 and 3 months postpartum, milk CRP was higher (1.46 ± 0.31 ng/mL; p < 0.001 and 1.69 ± 0.31 ng/mL; p < 0.001) in women with GDM than in women without GDM, whereas milk glucose (−5.23 ± 2.22 mg/dL; p = 0.02 and −5.70 ± 2.22; p = 0.01) and milk insulin (−0.38 ± 0.17 µIU/mL; p = 0.03 and −0.53 ± 0.17; p = 0.003) were lower in women with GDM. These significant associations remained similar after additional adjustment for maternal weight status and its changes. No difference was found for milk IL-6, leptin, and adiponectin. There was no evidence of association between these milk bioactive compounds and 1 h non-fasting oral glucose challenge serum glucose in the women without GDM. This prospective study provides evidence that potentially bioactive elements of human milk composition are altered in women with GDM.

Human Milk Glucose, Leptin, and Insulin Predict Cessation of Full Breastfeeding and Initiation of Formula Use.

Objective: We aimed to investigate prospective associations between milk bioactives related to metabolic health (glucose, insulin, leptin, C reactive protein [CRP], and interleukin 6 [IL-6]) and incident formula initiation at 3 and 6 months postpartum. Design: This study included 363 mother-infant dyads who were fully breastfed at 1 month and participated in the prospective Mothers and Infants Linked for Healthy Growth study from pregnancy to 6 months postpartum. Associations between milk glucose, leptin, insulin, CRP, and IL-6 at 1 and 3 months and incident formula feeding (FF) at 3 and 6 months, respectively, were tested using multiple logistic regression, adjusting for numerous potential confounders such as maternal age and prepregnancy body mass index. Results: At 3 months postpartum, 1-month glucose (odds ratio [OR] 0.45 [95% confidence interval (CI): 0.27-0.75], p ≤ 0.01) and smaller decreases in glucose from 1 to 3 months (OR 0.51 [95% CI: 0.28-0.92], p = 0.03) were associated with lower odds of FF, whereas 1-month leptin (OR 2.30 [95% CI: 1.30-4.07], p < 0.01) and larger increase in insulin (OR 1.86 [95% CI: 1.23-2.81], p < 0.01) and leptin (OR 2.17 [95% CI: 1.29-3.68], p < 0.01) from 1 to 3 months were associated with increased odds of FF. At 6 months, insulin increases (OR 2.08 [95% CI: 1.03-4.17], p = 0.04) were associated with higher odds of FF. Conclusions: In a cohort of women with established lactation, 1-month milk glucose, insulin, and leptin predicted initiation of FF at 3 months. Early milk composition may provide a window into mammary gland function, allowing identification of women at risk of not meeting their breastfeeding goals.

Maternal Dietary Intake of Total Fat, Saturated Fat, and Added Sugar Is Associated with Infant Adiposity and Weight Status at 6 mo of Age.

BACKGROUND: Whether current dietary guidelines are appropriate for pregnancy and lactation has not been well studied. Many women of reproductive age are not meeting recommendations for dietary components such as fat, added sugar, and fiber. OBJECTIVES: To assess associations between maternal dietary components during pregnancy and lactation and infant growth and adiposity at 6 mo of age. METHODS: Mother-infant dyads (n = 349) from the prospective, observational Mothers and Infants Linked for Healthy Growth study were included (100% fully breastfed for 1 mo; 75% to 6 mo). Daily intake of fat, fiber, and added sugar was obtained using the National Cancer Institute Diet History Questionnaire II during the third trimester of pregnancy and at 1 and 3 mo postpartum. Furthermore, intakes were categorized as meeting/exceeding 2015-2020 Dietary Guidelines for Americans. Multiple linear regression models adjusted for numerous potential confounders tested relations between dietary components and infant adiposity (via DXA) and growth parameters. Regression coefficients (ß) for continuous variables were expressed per SD to allow for comparison of effect sizes. RESULTS: Maternal intake of total fat and saturated fat was positively associated with infant percent body fat (%BF) (ß: 0.84 per SD, P = 0.04; ß: 0.96 per SD, P = 0.01, respectively). Added sugar intake was positively associated with infant weight-for-length z score (ß: 0.16 per SD, P = 0.02), and excessive added sugar intake was positively associated with %BF at 6 mo (ß: 0.75 per SD, P = 0.05). CONCLUSIONS: In a predominantly fully breastfeeding cohort of women, maternal intake of fat and added sugar during pregnancy and lactation were associated with small increases in infant adiposity and relative weight at 6 mo. Additional research is needed to determine if these relations persist later in infancy and if such elevations in adiposity are important for long-term obesity risk.

Association of Full Breastfeeding Duration with Postpartum Weight Retention in a Cohort of Predominantly Breastfeeding Women.

Full breastfeeding (FBF) is promoted as effective for losing pregnancy weight during the postpartum period. This study evaluated whether longer FBF is associated with lower maternal postpartum weight retention (PPWR) as compared to a shorter FBF duration. The MILK (Mothers and Infants Linked for Healthy Growth) study is an ongoing prospective cohort of 370 mother-infant dyads, all of whom fully breastfed their infants for at least 1 month. Breastfeeding status was subsequently self-reported by mothers at 3 and 6 months postpartum. Maternal PPWR was calculated as maternal weight measured at 1, 3, and 6 months postpartum minus maternal prepregnancy weight. Using linear mixed effects models, by 6 months postpartum, adjusted means ± standard errors for weight retention among mothers who fully breastfed for 1-3 (3.40 ± 1.16 kg), 3-6 (1.41 ± 0.69 kg), and ≥6 months (0.97 ± 0.32 kg) were estimated. Compared to mothers who reported FBF for 1-3 months, those who reported FBF for 3-6 months and ≥6 months both had lower PPWR over the period from 1 to 6 months postpartum (p = 0.04 and p < 0.01, respectively). However, PPWR from 3 to 6 months was not significantly different among those who reported FBF for 3-6 versus ≥6 months (p > 0.05). Interventions to promote FBF past 3 months may increase the likelihood of postpartum return to prepregnancy weight.

Higher Maternal Diet Quality during Pregnancy and Lactation Is Associated with Lower Infant Weight-For-Length, Body Fat Percent, and Fat Mass in Early Postnatal Life.

Maternal pregnancy nutrition influences fetal growth. Evidence is limited, however, on the relationship of maternal diet during pregnancy and lactation on infant postnatal growth and adiposity. Our purpose was to examine associations between maternal diet quality during pregnancy and lactation with offspring growth and body composition from birth to six months. Maternal diet quality was serially assessed in pregnancy and at one and three months postpartum, using the Healthy Eating Index⁻2015 in a cohort of 354 fully breastfeeding mother⁻infant dyads. Infant length-for-age (LAZ), weight-for-age (WAZ), and weight-for-length (WLZ) Z-scores were assessed at birth, one, three, and six months. Infant body fat percent (BF%), fat mass (FM), and fat-free mass (FFM) were measured at six months using dual-energy X-ray absorptiometry. Higher maternal diet quality from pregnancy through three months postpartum was associated with lower infant WLZ from birth to six months (p = 0.02) and BF% at six months (p ≤ 0.05). Higher maternal diet quality at one and three months postpartum was also associated with lower infant FM at six months (p < 0.01). In summary, maternal diet quality during pregnancy and lactation was inversely associated with infant relative weight and adiposity in early postnatal life. Additional research is needed to explore whether associations persist across the life course.