Pregnancy outcomes and relationship between maternal weight gain and fetal birth weight in Korean pregnant women at risk for gestational diabetes

Objective: We evaluated pregnancy outcomes in women at risk for gestational diabetes and examined associations of maternal weight gain and fetal birth weight. Methods: A retrospective analysis of 667 women who gave a full term singleton birth and had a blood glucose level ≥140 mg/dL on a 50 g glucose challenge test between July 1, 2007 and December 31, 2008 at CHA University (CHA Gangnam Medical Center, Korea). Based on the results of 3-hour glucose tolerance test (OGTT), women were divided into three groups: normal glucose tolerance (no high value), impaired glucose tolerance (1 high value), and gestational diabetes (GDM: ≥2 high value). Maternal characteristics and pregnancy outcomes were compared among the three groups. Results: The women with more positve values on OGTT showed significantly older age and more family diabetes history and past GDM history, and higher pre-pregnant body mass index and obesity. However, total weight gain during pregnancy was inversely correlated with the OGTT values. The primary cesarean section rate and fetal birth weight were slightly higher in GDM group without significance. Macrosomia tended to be more frequent in GDM group than other group (odds ratio, 2.28; 95% confidence interval, 1.05-4.97; P=0.052). Maternal weight gain was positively correlated with fetal birth weight in all groups(r=0.175, P=0.000). Conclusion: Higher numbers of positive OGTT are associated with more risk factors such as age, obesity and show a tendency to have a macrosomic fetus. Associated with maternal diabetic risk, maternal weight gain may be an affecting factor for fetal birth weight.