The effect of maternal obesity on pregnancy outcomes in women with gestational diabetes

Objective. To examine the impact of maternal obesity on maternal and neonatal outcomes in pregnancies complicated with gestational diabetes mellitus (GDM). Methods. Women with singleton pregnancies and GDM enrolled in an outpatient GDM education, surveillance and management program were identified. Maternal and neonatal pregnancy outcomes were compared for obese (pre-pregnancy BMI ≥30 kg/m²) and non-obese (pre-pregnancy BMI < 30 kg/m ²) women and for women across five increasing prepregnancy BMI categories. Results. A total of 3798 patients were identified. Maternal obesity was significantly associated with the need for oral hypoglycemic agents or insulin, development of pregnancy-related hypertension, interventional delivery, and cesarean delivery. Adverse neonatal outcomes were also significantly increased including stillbirth, macrosomia, shoulder dystocia, need for NICU admission, hypoglycemia, and jaundice. When looking across five increasing BMI categories, increasing BMI was significantly associated with the same adverse maternal and neonatal outcomes. Conclusion. In women with GDM, increasing maternal BMI is significantly associated with worse maternal and neonatal outcomes.