The use of oral antidiabetic medications in gestational diabetes mellitus.

Gestational diabetes mellitus (GDM) is defined as carbohydrate intolerance with onset or first recognition during pregnancy. When medical nutrition therapy is not successful in maintaining target glucose values during pregnancy complicated by GDM, medication is required. Insulin has been the traditional treatment under such circumstances. The use of oral antidiabetic medications in the management of gestational diabetes has increased over the past several years. Recent studies have shown the equivalence to insulin of both glyburide and metformin in terms of pregnancy outcomes in GDM. However, both agents have been shown to cross the placenta to the fetus, and thus they should be used with caution and patients counseled appropriately.