title: Metformin safety in the management of gestational diabetes.
abstract: OBJECTIVE
  The use of metformin in pregnant women is still controversial, despite the increasing reports on metformin's safety and effectiveness. We aimed to evaluate the maternal and neonatal safety of metformin in subjects with gestational diabetes mellitus (GDM).
  
  
  METHODS
  We retrospectively reviewed the clinical records of 186 pregnancies complicated with GDM surveilled at Hospital de Santa Maria, Lisboa, between 2011 and 2012. The maternal and neonatal outcomes of 32 females who took metformin during pregnancy were compared with 121 females controlled with diet and 33 insulin-treated females.
  
  
  RESULTS
  Of the 186 GDM subjects, 32 (17.2%) received metformin during pregnancy. No statistical differences between the diet and metformin groups were found with regard to the rates of abortion, prematurity, preeclampsia, macrosomy, small-for-gestational-age (SGA) or large-for-gestational-age (LGA) newborns, cesarean deliveries, neonatal intensive care unit (NICU) admissions, and birth malformations or neonatal injuries. Similarly, there were no differences between the metformin and insulin groups with regard to the referred outcomes. No abortions or perinatal deaths were recorded in the metformin group. Ten out of 32 metformin patients required additional insulin.
  
  
  CONCLUSIONS
  This retrospective study suggests that metformin is a safe alternative or additional treatment to insulin in females with GDM. Metformin was not associated with a higher risk of maternal or neonatal complications when compared to the insulin or diet groups.
authors.affiliation: Department of Endocrinology, Instituto Português de Oncologia de Lisboa.
authors.forename: Pedro
authors.initials: P
authors.lastname: Marques
authors.affiliation: Department of Endocrinology, Hospital de Santa Maria, CHLN, Lisboa, Portugal.
authors.forename: Maria Raquel
authors.initials: MR
authors.lastname: Carvalho
authors.affiliation: Department of Obstetrics and Gynecology, Hospital de Santa Maria, CHLN, Lisboa, Portugal.
authors.forename: Luísa
authors.initials: L
authors.lastname: Pinto
authors.affiliation: Department of Endocrinology, Hospital de Santa Maria, CHLN, Lisboa, Portugal.
authors.forename: Sílvia
authors.initials: S
authors.lastname: Guerra