Background Pregestational diabetes is associated with low prevalence of breastfeeding due to low rates of intent, delayed lactogenesis, and early infant separation. It is hypothesized that the perceived need for formula supplementation due to neonatal hypoglycemia, coupled with maternal low early milk supply, is a barrier to breastfeeding initiation. Whether there is an association between neonatal hypoglycemia and breastfeeding is unknown. We evaluated associations between neonatal hypoglycemia and breastfeeding. Methods This is a secondary analysis of a randomized control trial of metformin versus placebo plus insulin in participants with type 2 diabetes. We included participants who delivered a liveborn neonate, endorsed intention to breastfeed, and had neonatal hypoglycemia data available. A breastfeeding questionnaire was administered at 30-days postpartum, and outcomes were compared between neonates with and without hypoglycemia The primary outcome was prevalence of exclusive, partial or no breastfeeding at 30-days postpartum. Secondary outcomes included time to breastfeeding cessation and contributing factors. Characteristics were compared with Chi-square, t-tests or Wilcoxon tests. Results 420 participants in the primary study (53%) completed an antepartum survey including a question about intent to breastfeed. After exclusion criteria were applied, 370 (91%) of 405 possible participants reported intention to breastfeed. Among these 370 who met criteria and had intention to breastfeed, 265 (72%) responded to the 30-day postpartum questionnaire. Of these 265, 114 (43%) had neonatal hypoglycemia and 151 (57.0%) did not. Prevalence of not breastfeeding (35% vs 37%), exclusive breastfeeding (18% vs 13%), and partial breastfeeding (47% vs 50%) did not differ between neonates with and without hypoglycemia (p = 0.51). This persisted in a NICU admitted subgroup (p = 0.29). Participants who stopped breastfeeding did so on average at 2.6-2.8 weeks (p = 0.76). Conclusions This study found no impact of neonatal hypoglycemia on 30-day postpartum breastfeeding prevalence among participants with diabetes.
Rogerson et al. (2026) studied this question.