Gestational weight gain and pregnancy outcomes in women with type 1 and type 2 diabetes mellitus

AimsWe aimed to explore the relationship between gestational weight gain (GWG) after Institute of Medicine (IOM) and pregnancy outcomes in women with type 1 and type 2 diabetes.MethodsRetrospective cohort study at a tertiary medical center (1981-2011). Outcome variables: 2 maternal and 14 fetal. Main exposure variable: GWG according to IOM. We calculated crude and adjusted ORs as well as population attributable (PAF) and preventable fractions (PPF) for significant positive and negative associations, respectively.ResultsWe evaluated 633 pregnant women with type 1 or type 2 diabetes. GWG was insufficient (iGWG) in 16.7% and excessive (eGWG) in 50.7%. In the adjusted analysis, GWG according to IOM was significantly associated with maternal outcomes (pregnancy-induced hypertension and cesarean delivery) and four fetal outcomes (large-for-gestational age, macrosomia, small-for-gestational age and neonatal respiratory distress). The association with large-for-gestational age newborns was negative for iGWG (0.48, CI 95% 0.25-0.94) and positive for eGWG (1.76, CI 95% 1.18-2.63). In addition, iGWG was associated with a higher risk of small-for-gestational age newborns and respiratory distress and eGWG with a higher risk of pregnancy-induced hypertension, caesarean delivery and macrosomia. PAF and PPF ranged from the 20.4% PPF of iGWG for large-for-gestational age to 56.5% PAF of eGWG for macrosomia.ConclusionIn this cohort of women with type 1 or type 2 diabetes, inadequate GWG after IOM was associated with adverse pregnancy outcomes; associations were unfavorable for eGWG and mixed for iGWG. The attributable fractions were not moderate, pointing to the potential impact of modifying inadequate GWG.