Maternal Glycemic Control and Hypoglycemia in Type 1 Diabetic Pregnancy: A randomized trial of insulin aspart versus human insulin in 322 pregnant women

OBJECTIVE —To assess the safety and efficacy of insulin aspart (IAsp) versus regular human insulin (HI) in basal-bolus therapy with NPH insulin in pregnant women with type 1 diabetes. RESEARCH DESIGN AND METHODS —Subjects ( n = 322) who were pregnant or planning pregnancy were randomized to IAsp or HI as meal-time insulin in an open-label, parallel-group, multicenter study. Subjects had A1C ≤8% at confirmation of pregnancy. Insulin doses were titrated toward predefined glucose targets and A1C RESULTS —Major hypoglycemia occurred at a rate of 1.4 vs. 2.1 episodes/year exposure with IAsp and HI, respectively (relative risk 0.720 [95% CI 0.36–1.46]). Risk of major/major nocturnal hypoglycemia was 52% (RR 0.48 [0.20–1.143]; P = NS) lower with IAsp compared with HI. A1C was comparable with human insulin in second (IAsp-HI −0.04 [−0.18 to 0.11]) and third (−0.08 [−0.23 to 0.06]) trimesters. A total of 80% of subjects achieved an A1C ≤6.5%. At the end of first and third trimesters, average postprandial plasma glucose increments were significantly lower with IAsp than HI ( P = 0.003 and P = 0.044, respectively), as were mean plasma glucose levels 90 min after breakfast ( P = 0.044 and P = 0.001, respectively). Maternal safety profiles and pregnancy outcomes were similar between treatments. CONCLUSIONS —IAsp is at least as safe and effective as HI when used in basal-bolus therapy with NPH insulin in pregnant women with type 1 diabetes and may potentially offer some benefits in terms of postprandial glucose control and preventing severe hypoglycemia.