Asymmetric large for gestational age newborns in pregnancies complicated by diabetes mellitus: is maternal obesity a culprit?

Objective: Evaluate the association between body mass index (BMI) and the delivery of an asymmetrically large for gestational age (A-LGA) newborn in women with diabetes. Methods: Retrospective analysis of 306 pregnancies complicated by Type 1 and 55 by Type 2 diabetes. Results: The prevalence of Type 1 and Type 2 diabetics delivering large for gestational age (LGA) infants was 42% and 49%, respectively. Of these 49% and 55% were A-LGA, respectively. Pre-pregnancy BMI was not associated with increased odds of delivering an A-LGA newborn in women with Type 1 or 2 diabetes. However, in Type 1 diabetics, each one-pound increase in maternal weight during pregnancy resulted in 4% increased odds of delivering an A-LGA newborn. For Type 2 diabetics, the odds of delivering an A-LGA infant was decreased by 10% for each 0.1 unit/kg increase in insulin dose. Conclusion: Although there is a known association between obesity and LGA in women with diabetes, we found that overweight and obese women with Type 1 or Type 2 diabetes do not have increased odds of delivering an A-LGA newborn. However, insulin dose in Type 2 diabetes and maternal weight gain in Type 1 diabetes were significantly associated with the odds of delivering an A-LGA neonate.