OBJECTIVE To investigate lipid levels in former gestational diabetic mothers, 5-6 years postpartum, and to evaluate the relationship of these values to glucose, insulin, BMI, and blood pressure. METHODS The subjects studied were 56 former gestational diabetic mothers and 48 control mothers 5-6 years postpartum. Two hours after a 50-g carbohydrate meal, total cholesterol (TC), triglycerides (TG), HDL and LDL cholesterol, glucose, and insulin were measured and compared between the two groups (analysis of variance). BMI and blood pressure were also evaluated. The risk of finding an abnormal metabolic, anthropometric, or hemodynamic parameter in either group was assessed (chi 2 analysis and Fisher's exact test). Correlation coefficients were assessed between the lipids versus insulin, glucose, BMI, and blood pressure. RESULTS Mean TC, TG, LDL cholesterol, glucose, and systolic blood pressure were significantly higher in the gestational diabetic mothers than in the control mothers. In addition, there was greater likelihood of finding an abnormal TC > or = 5.17 mmol/l, LDL cholesterol > or = 4.14 mmol/l, and systolic blood pressure > 140 mmHg in gestational diabetic mothers. Triglycerides correlated with BMI, insulin, systolic and diastolic blood pressure, and HDL cholesterol correlated inversely with insulin in gestational diabetic mothers. CONCLUSIONS We conclude that at 5-6 years postpartum, former gestational diabetic mothers demonstrate changes in lipid levels that differ from control mothers and that specific lipids correlate with cardiovascular risk factors. Further study is needed to evaluate gestational diabetic mothers for the development of cardiovascular risk factors including insulin resistance.