[Fetal growth and glycemic control in type 1 diabetes pregnancy].

INTRODUCTION: Conflicting results have been reported with respect to the relationship between direct or indirect measures of glycemic control in mothers with type 1 diabetes and macrosomia.

OBJECTIVE: To evaluate the frequency of LGA babies in type 1 diabetic pregnancies and analyse the influence of some maternal characteristics and glucose control in oversized babies.

MATERIAL AND METHODS: A retrospective study of 18 pregnant women with type 1 diabetes mellitus was performed. It was divided in two groups: group 1 (G1- n=9)--pregnant women with LGA babies and group 2 (G2- n=9)--pregnant women with AGA (Appropriate weight for gestational age) babies. We evaluate the follow parameters: HbA1c in the third trimester of pregnancy, fasting and 1 h postprandial capillary glucose levels, pregestational BMI, maternal age, duration of Diabetes mellitus, weight gain during pregnancy, microvascular diabetes complications (retinopathy and nefropathy), and type of delivery. We defined LGA birth weight over the 90 centile.

RESULTS: LGA babies occurred in 50% of gestations. We did not find any statistical differences in maternal age, diabetes mellitus duration, pregestational BMI, weight gain during pregnancy, microvascular diabetes complications, HbA1c levels (medium value in the two groups 6,5%). The glucose fasting values were higher in G1: 95,7 +/- 31.7 mg/ dl, vs G2: 83.3 +/- 17.1 mg/dl without, however, reaching statistically significant differences. There was statically differences in postprandial glucose values G1: 160.3 +/- 60.2 mg/dl vs G2: 111.9 +/- 27.1 mg/dl -- p= 0.043.

CONCLUSIONS: The frequency of LGA babies was elevated 50% in type 1 diabetic pregnancies, although normal HbA1c values. Thus we conclude that the 1 h postprandial glucose levels should be considered a strong predictor of fetal growth.