Does Antenatal Expressing Affect Onset of Lactogenesis for Women With Diabetes? Results From a Randomised Controlled Trial and Cohort Study.

Background: Previously it was recognised onset of Lactogenesis II was delayed in women with Type I diabetes compared to women without diabetes, but the effect of gestational diabetes was unclear. Some clinicians suggest pregnant women with diabetes express breastmilk in late pregnancy to hasten onset of Lactogenesis II.

Aims: To confirm if Lactogenesis II occurs later in women with diabetes in pregnancy, and test if advice to express antenatally hastens Lactogenesis II.

Materials And Methods: Data from the DAME (Diabetes Antenatal Milk Expression) randomised controlled trial collected at recruitment and 2 weeks postpartum were compared with a concurrent purposively recruited cohort of women without diabetes in pregnancy. Timing of lactogenesis and adjusted percentage differences were calculated. Study sample was women from both studies with complete data for included measures to assess onset of Lactogenesis II (maternal perception).

Results: Delayed onset of lactation (≥ 72 h postpartum) was similar in DAME trial arms: standard care 58.6% (143/244); antenatal expressing 55.8% (148/265) but lower in comparison cohort 46.9% (90/192). Percentage difference between groups (adjusted for parity, delivery mode, BMI and gestation): DAME standard arm and comparison cohort 12.3% (95% CI 2.6%-22.0%; p = 0.01) DAME intervention arm and comparison cohort 8.3% (95% CI -1.2%-17.8%; p = 0.09) DAME standard care and intervention 4.0% (95% CI -4.5%-12.5%; p = 0.35).

Conclusions: Lactogenesis II occurs later for women with diabetes in pregnancy than women without diabetes. Our findings do not provide evidence that antenatal expressing hastens onset of lactation in women with diabetes in pregnancy.

Trial Registration: ClinicalTrials.gov identifier: ACTRN12611000217909.