The relationship between patterns of insulin secretion and risks of gestational diabetes mellitus

Objective To evaluate patterns of insulin secretion in pregnancy and analyze the association between insulin patterns and risks of gestational diabetes mellitus (GDM). Methods A prospective study was conducted to collect and analyze pregnant women's materials from January 2015 to December 2018. Pregnant women were grouped according to results of 75-g oral glucose tolerance test at 24-28 weeks of pregnancy: normal glucose tolerance (NGT) and GDM. Insulin secretion patterns were based on the time of peak(s) and shape of insulin secretion curve. The relationship between insulin secretion patterns and pregnant outcomes was analyzed. Results A total of 2432 pregnant women met the inclusion criteria during the study period. Among them, 737 (30.3%) women were grouped as GDM and 1695 (69.7%) as NGT. Type I insulin secretion represented the early phase of insulin secretion (peak time at 30 or 60 minutes), while type II represented the delayed peak of insulin secretion (peak time at 120 or 180 minutes). Logistic regression analysis showed that type II insulin secretion was a risk factor of pre-eclampsia, large-for-gestational-age, and neonatal hypoglycemia. Conclusion The delayed insulin peak is a useful marker for risk of GDM and adverse pregnant outcomes in women with GDM.