With oral contraceptives (OCs), estrogen and progestogen doses, as well as the type of progestogen used, seem to directly affect glucose tolerance and insulin resistance. Other factors that influence these parameters are a patient's weight and age, family history of diabetes, and previous gestational diabetes. In normal-weight women with previous gestational diabetes, low-dose OCs do not appear to directly affect glucose tolerance, plasma insulin levels, or insulin binding to monocytes. This paper reports the initial data from a study employing low-dose OC formulations in obese patients with a history of either Class A1 or A2 gestational diabetes. Although results are preliminary, they do suggest that Ovcon 35, a low-dose norethindrone-containing OC, may be safe in Class A1 diabetics; in Class A2 diabetics, Ovcon 35 is associated with significantly less change in oral glucose tolerance at 3 months than is the triphasic Triphasil.