High-intensity breastfeeding improves insulin sensitivity during early post-partum period in obese women with gestational diabetes.

Abstract

To investigate whether high-intensity breastfeeding (HIB) reduces insulin resistance during early post-partum period in women with gestational diabetes (GDM), independent of post-partum weight change (PWC). In this multicentre prospective study, we included Japanese women with GDM who underwent a 75-g oral glucose tolerance test (OGTT) during early post-partum. We measured plasma insulin during OGTT to obtain a homeostasis model of assessment of insulin resistance (HOMA-IR). We defined the condition in which infants were fed by breastfeeding alone or greater than or equal to 80% of the volume as HIB, and other statuses, including partial and nonbreastfeeding, as non-HIB. We investigated the association between post-partum HOMA-IR and the breastfeeding status after adjusting for confounders including PWC. Among 222 women with GDM who underwent the OGTT at 7.9±2.3weeks post-partum with a PWC of -7.8±3.4kg, although the rate of abnormal glucose tolerance (prediabetes and diabetes) did not differ between the groups (33% vs 32%), the HOMA-IR in the HIB women (n=166) was significantly lower than that in the non-HIB women (n=56) (1.12±0.85 vs 1.72±1.43, P=0.0002). The effect of the HIB was independently associated with lower HOMA-IR after adjusting for confounders including PMC. However, the subgroup analysis according to their pre-pregnancy obesity states showed that the effect was seen only in the obese subjects (BMI≥25). In obese Japanese women with GDM, HIB has a significant effect in reducing insulin resistance during early post-partum, independent of the post-partum weight loss.