Metformin and insulin in the management of gestational diabetes mellitus: preliminary results of a comparison.

Abstract

To compare glycemic control and neonatal outcomes in women with gestational diabetes mellitus (GDM) treated with metformin vs. insulin.Women with GDM not controlled with diet and exercise were randomized to metformin (n = 32) or insulin (n = 31). The levels of glycemic control as well as maternal/neonatal complications were evaluated.The mean (+/- SD) fasting and 2-hour postprandial blood glucose did not differ statistically between the 2 treatment groups. No patient failed metformin and required insulin. The majority (27/32) were easily controlled on the initial dosage (500 mg twice a day). Gestational age at entry and delivery (p = 0.077, 0.412) were similar. The difference in the rate of cesarean delivery was not statistically significant between the 2 groups (p = 0.102). Neonatal statistics were also not different between the metformin and insulin groups: birth weight, Apgar score at 5 minutes, respiratory distress syndrome, hyperbilirubinemia, neonatal hypoglycemia and neonatal intensive care unit admission (p = 0.144-0.373).Based on these preliminary data, metformin appears to be an effective alternative to insulin in the treatment of GDM.