Maternal obesity is a major risk factor for large-for-gestational-infants in pregnancies complicated by gestational diabetes.

OBJECTIVES: Our aim was to evaluate the relative contribution of maternal weight, GDM severity and glycemic control in women with gestational diabetes (GDM) on the prevalence of LGA infants.

METHODS: A total of 233 women with GDM were classified according to the fasting and/or postprandial glucose levels as in "good" or "poor" glycemic control. Severity of GDM was categorized using fasting plasma glucose on the 3-h 100 g oral glucose tolerance test (OGTT).

RESULTS: The incidence of LGA infants was significantly higher in obese women than in those with lower BMI. There was no significant correlation between GDM severity or level of glycemic control and birth weight or proportion of LGA infants. On multivariate regression analyses, only maternal weight at delivery and fasting glucose level on OGTT were found to be independently and significantly associated with the birth weight, and only maternal weight at delivery was a significant and independent predictor of LGA infants.

CONCLUSIONS: Both the GDM severity and maternal weight are independent predictors of infants' birth weights. Maternal weight at delivery is a major risk factor for LGA infants.