Early Feeding Patterns After Pregnancies Complicated by Gestational Diabetes Mellitus ^†

Abstract

Gestational diabetes mellitus (GDM) has been associated with suboptimal breastfeeding outcomes, including low milk supply, and the aetiology of this is not well understood. As postpartum frequency of milk removal is critical to the establishment of milk production, we compared the early feeding patterns of breastfeeding women with and without GDM. Women with GDM (n = 54) and without GDM (n = 54) provided detailed birth and feeding data within 48 hours of birth and at one and three weeks postpartum and measured their 24 h milk production. Sociodemographic characteristics were similar between groups (p > 0.05), and GDM was associated with an earlier birth gestation (38.5 ± 0.7 vs. 39.5 ± 0.2 weeks, p < 0.001). The median timing of breastfeeding initiation was < 1 h for both groups, yet breastfeeding frequency in the first 24 h was lower in the GDM group (5.9 ± 3.5 vs. 7.8 ± 4.4, p = 0.016). Both in-hospital commercial milk formula supplementation (57% vs. 26%, p < 0.001) and delayed secretory activation beyond day 4 postpartum (32% vs. 7%, p = 0.003) were more prevalent in the GDM group. Combined breastfeeding and breast expression frequencies were similar between groups in the first 24 h (p = 0.48) and at one week (p = 0.46) and three weeks postpartum (p = 0.05). Low milk production (<600 mL/24 h) was more prevalent in the GDM group, i.e., 19/50 (38%) compared to those without GDM, i.e., 8/50 (16%), (p = 0.006). Furthermore, four participants with GDM had weaned/withdrawn due to low milk supply, i.e., 23/54 (43%). The prevalence of low milk supply, despite frequent breastfeeding and breast expression across the first three weeks postpartum, suggests that endocrine factors may impair the autocrine control of milk production in some women with GDM.