Maternal and fetal outcome in women with type 2 versus type 1 diabetes mellitus: a systematic review and metaanalysis.

ABSTRACT

CONTEXT Glycemic disturbance is usually less severe in pregnant women with type 2 than in those with type 1 diabetes mellitus (DM). Nevertheless, a worse perinatal outcome in women with type 2 DM has been reported in some studies. OBJECTIVE: Our objective was to review maternal and fetal outcomes in pregnant women with type 2 vs. type 1 DM. STUDY SELECTION We conducted a systematic review of papers providing original data on pregnancy outcomes in both type 2 and type 1 DM (Medline search of the period January 1, 1987, to June 30, 2008). Two independent investigators considered papers for eligibility, and a third one solved discrepancies. DATA EXTRACTION Metaanalysis tools were used to compare four main outcomes (major congenital malformations, stillbirth, and neonatal and perinatal mortality) and 15 secondary ones (five maternal, 10 fetal). Meta-analysis of Observational Studies in Epidemiology (MOOSE) guidelines were used to assess quality. DATA SYNTHESIS: Thirty-three studies qualified for inclusion of 3743 citations retrieved. Women with type 2 DM had lower glycated hemoglobin (HbA1c) at booking and throughout pregnancy but a higher risk of perinatal mortality [odds ratio (OR) 1.50, 95% confidence interval (CI) 1.15-1.96] without significant differences in the rates of major congenital malformations, stillbirth, and neonatal mortality. As to secondary outcomes, women with type 2 DM had less diabetic ketoacidosis (OR 0.09, 95% CI 0.02-0.34) and cesarean section (OR 0.80, 95% CI 0.59-0.94) without differences in other outcomes. CONCLUSIONS: Despite a milder glycemic disturbance, women with type 2 DM had no better perinatal outcomes than those with type 1, indicating that type 2 DM in pregnancy is a serious condition.