Gestational diabetes and pre-eclampsia: common antecedents?

OBJECTIVE To evaluate commonality of risk factor profiles of women who develop gestational diabetes and pre-eclampsia. METHODS Prospective cohort study in prenatal clinics of the Brazilian Unified Health System in six state capitals. 4.766 pregnant women between 20 to 48 years old were consecutively enrolled between 20th and 28th gestational weeks. Smoking habits and traditional risk factors for pre-eclampsia and gestational diabetes were obtained by the interview at enrollment. Gestational diabetes was diagnosed using a 75-g oral glucose tolerance test and pre-eclampsia through chart review. RESULTS Both gestational diabetes and pre-eclampsia were associated with age (OR 2.07; 95% CI 1.65-2.23 and OR 1.55; 95% CI 1.08-2.23, respectively), pre-pregnancy body mass index (OR 1.62; 95% CI 1.40-3.53 and OR 1.83; 95% CI 1.52-4.80, respectively) and weight gain in early pregnancy (OR 1.28; 95% CI 1.12-1.47 and OR 1.27; 95% CI 1.06-1.52, respectively). Lower odds of gestational diabetes (OR 0.31; 95% CI 0.22-0.44) and pre-eclampsia (OR 0.36; 95% CI 0.20-0.51) were observed in nulliparous women who have smoked during pregnancy. CONCLUSIONS Gestational diabetes and pre-eclampsia share a pattern of risk factors, suggesting the possibility of common aetiology.