Breastfeeding outcomes at 3 months for women with diabetes in pregnancy: Findings from the Diabetes and Antenatal Milk Expressing randomized controlled trial

Background: Women with diabetes in pregnancy have decreased exclusivity and duration of breastfeeding compared with women without diabetes, and their infants are at increased risk of hypoglycemia. Clinicians often suggest pregnant women with diabetes to express breastmilk, and studies have reported increased breastfeeding exclusivity in the early postnatal period for patients who have expressed. Little is known about longer term outcomes. We investigated whether advising low-risk women with diabetes in pregnancy to express beginning at 36 weeks of pregnancy increased exclusivity and maintenance of breastfeeding at 3 months. Methods: We conducted a multicenter, two-group, randomized controlled trial at six hospitals in Melbourne, Australia, between 2011 and 2015. Women were randomized to either standard maternity care or advised to hand express for 10 min twice daily, in addition to standard care. Women were telephoned at 12–13 weeks postpartum and asked a series of questions about feeding their baby, perceptions of their milk supply, and other health outcomes. Results: Of 631 women in the study, data for 570 (90%) were analyzed at 12–13 weeks. After adjustment, we found no evidence that women allocated to antenatal expressing were more likely to be giving only breastmilk (aRR 1.07 [95% CI 0.92–1.22]) or any breastmilk (aRR 0.99 [95% CI 0.92–1.06]) at 12–13 weeks postpartum compared with women in the standard care group. Conclusion: While the practice of antenatal expression for low-risk women with diabetes during pregnancy is promising for increasing exclusivity of breastmilk feeding in hospital, at 12–13 weeks, there was no association with breastfeeding outcomes.