Breastfeeding Is Associated With Lower Prevalence of Metabolic Syndrome in Women With Recent Gestational Diabetes in the Early Postpartum Period

Introduction: Women with gestational diabetes (GD) are at increased risk of future cardiovascular disease. The identification of factors that reduce metabolic syndrome (MetS) is important to improve cardiovascular outcomes. MetS has been shown to be associated with breastfeeding in women remote from pregnancy. We examined the association of breastfeeding with MetS in women with recent GD in the very early postpartum (pp) period. Methods: We performed a secondary analysis of the Balance After Baby (BAB) program which enrolled women with recent GD. GD was defined by Carpenter-Coustan criteria, a 50 gram glucose load test >200 mg/dL or by clinician diagnosis. Data collected during an early (~6 weeks) pp visit was used in this analysis. At this visit, weight, height, waist circumference (WC), blood pressure (BP), fasting plasma glucose (FPG) and lipid panel were obtained. MetS was classified per NCEP III. We defined breastfeeding as currently breastfeeding or not currently breastfeeding. We performed Student’s t-tests and Wilcoxon rank-sum tests as appropriate, and fit logistic and linear regression models. Models were adjusted for age, race/ethnicity, low household income, pre-pregnancy BMI, and weeks since delivery. An exploratory model further adjusted for postpartum weight retention. Results: Of 181 women enrolled in BAB, 178 were included in this analysis (3 excluded for missing lipid panels). The mean (± SD) age of participants was 33 ± 5 years and were 8.0 ± 1.8 weeks since delivery. Thirty-four % were Hispanic. Of non-Hispanics, 31.5% were White, 18.5% Asian and 12.9% Black/African American. The prevalence of MetS was 42.9% in women not breastfeeding versus 17.1% in women breastfeeding (P < 0.001; adjusted odds ratio [aOR] 0.16 [95% CI 0.06–0.41]). Breastfeeding women had significantly lower odds of FPG ≥100 mg/dL (aOR 0.36 [95% CI 0.14–0.95], p=0.039), HDL <50 mg/dL (aOR 0.19 [95% CI 0.08–0.46], p<0.001), and triglycerides (TG) ≥150 mg/dL (aOR 0.26 [95% CI 0.10–0.66], p=0.005). There was no significant difference in WC or BP between groups. All ORs remained significant after adjusting for weight retention. When evaluated as continuous variables, WC, FPG, and TG were significantly lower and HDL significantly higher in women breastfeeding in the early pp period (vs not breastfeeding). Conclusion: In a diverse population of women with recent GD, there was a lower prevalence of MetS in women breastfeeding compared to those not breastfeeding in the early postpartum period. This study extends the findings of an association of breastfeeding with MetS previously reported at times remote from pregnancy. Further studies are needed to determine if there is a protective role of breastfeeding on the risk of MetS.