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

Abstract

Aims: We 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.

Methods: Retrospective 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.

Results: We 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.

Conclusion: In 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.

Keywords: Gestational weight gain; Institute of Medicine; Pregnancy outcomes; Type 1 diabetes; Type 2 diabetes.