Gestational Diabetes Treatment and its Impact on Pregnancy and Neonatal Complications

Introduction: The incidence of gestational diabetes (GD) has been increasing, mostly due to better diagnostic tools and recent diagnostic criteria, allowing early screening. This study aims to evaluate the impact of GD therapeutics on the occurrence of cesarean sections and pregnancy and neonatal complications. Methods: This is a cohort study of GD pregnant women followed-up in various Portuguese hospitals and maternities, diagnosed between 2014 and 2018. Our sample was 15 089 pregnant women, divided in four groups, based on the therapeutics used to treat GD: diet and exercise, insulin, oral hypoglycemic drug (OHD) and insulin+OHD. Results: The insulin group showed higher risk of caesarean section, neonatal hypoglycemia, neonatal hyperbilirubinemia and large for gestational age (LGA) newborns. Regarding the OHD group, there was higher probability for hydramnios and trauma at delivery and lesser risk for low birth weight and small for gestational age newborns (SGA). Lastly, the OHD+insulin group exhibited more likelihood to maternal and neonatal morbidity, like neonatal hypoglycemia, hyperbilirubinemia, trauma at delivery, and LGA newborns. Conclusion: The simultaneous administration of insulin and OHD was more likely associated with pregnancy and neonatal complications. However, this group already had pre-conception characteristics that predisposed to complications (more advanced maternal age, higher previous BMI, familial history of diabetes, previous GD and/or macrosomia) and worse therapeutic adherence leading to a badly controlled glycemic profile. Therefore, these complications may be the result of the presence of previous characteristics and a glycemic profile that is difficult to control, rather than the use of insulin and OHD, per se.