Effect of breastfeeding on postpartum glucose regulation in Chinese women with recent gestational diabetes

Abstract

Gestational diabetes mellitus (GDM) is associated with adverse maternal and fetal outcomes and increases subsequent risk of Type II diabetes. Globally, the prevalence of GDM varies, but Asian populations have substantially higher rates, with reported prevalence rates ranging from 12 to 15%. When compared with non-lactating women, new mothers who are breastfeeding have improved insulin sensitivity and glucose tolerance. However, few studies have examined the effect of breastfeeding on postpartum maternal glucose tolerance in women with recent GDM. Thus, the aim of this study was to examine the effect of breastfeeding on postpartum glucose tolerance at 6 weeks postpartum among Chinese women with recent GDM. We recruited 830 women diagnosed with GDM during pregnancy from the obstetric outpatient setting of three public hospitals in Hong Kong. We computed the odds of Impaired Fasting Glucose (IFG) according to the infant feeding pattern (exclusive, any and no breastfeeding) at 6 weeks postpartum using logistic regression analysis. At 6 weeks postpartum, 36.4%, 43.1%, and 20.5% of participants were giving exclusive, partial, and no breast milk feedings, respectively. Mean fasting blood glucose (FBG) was 4.61 (SD=0.65), 4.83 (SD=0.58) and 4.97 (SD=0.60) in participants feeding exclusive, partial and no breast milk (p <.001). When compared with participants exclusively breastfeeding, the odds of IFG were substantially higher in participants partially breastfeeding (OR=10.5; 95% CI 1.33-82.7) and exclusively formula feeding (OR=17.3; 95% CI 2.09-142.7). As little as 2 weeks of exclusive breastfeeding was associated with reduced odds of IFG (OR=0.15; 95% CI 0.04-0.53). Exclusive breastfeeding reduces postpartum fasting blood glucose in mothers with GDM. Improving postpartum glucose tolerance in women with GDM could help to offset the later onset of Type II diabetes. In women with GDM breastfeeding is a modifiable risk factor for Type II diabetes and should be encouraged and supported among this high-risk group.