Pharmacological therapy in gestational diabetes - a comparison between insulin and oral therapy

The appropriate medical treatment for gestational diabetes mellitus (GDM) is controversial and recommendations vary between different organizations.

To compare the safety and efficacy of glyburide and insulin as treatments for GDM.

Retrospective analysis of all pregnant women diagnosed with GDM and treated with either glyburide or insulin. Demographic features, clinical characteristics, maternal and neonatal outcomes were compared according to type of pharmacological treatment.

Included in the study were 323 women, of whom 269 (83.28%) were treated with glyburide and 54 (16.72%) with insulin. There were no significant differences between the groups, apart from a higher one-hour oral glucose tolerance test (OGTT) value (191.80 mg/dl in the glyburide group, 204.33 in the insulin group, p = .01). Optimal glucose control was achieved in 130 women in the glyburide group (48.32%) and 15 in the insulin group (27.77%), p = .007. This difference remained significant after adjustment for age, BMI, and fasting glucose during OGTT (aOR = 2.22). Mean gestational weight gain was lower in the glyburide group vs. insulin group (10.01 vs. 11.99 kg, p = .048). Apart from higher maternal hypoglycemia rate (12.64% in glyburide group vs. 1.85% in insulin group, p = .016), there were no other differences in maternal and neonatal outcomes between the groups. Glyburide failure rate was 13.38%, and associated with higher fasting OGTT value (100.70 mg/dl in glyburide failure group vs. 94.67 mg/dl in the glyburide treatment until delivery group, p = .041).

Glyburide is at least as safe and effective as insulin except for higher rates of maternal hypoglycemia. Considering its advantages compared to insulin (ease of use and storage, increased patient responsiveness, and lower cost), it may be considered as first line treatment in GDM, especially when fasting OGTT value is not high.