OBJECTIVE -To compare management based on maternal glycemic criteria with management based on relaxed glycemic criteria and fetal abdominal circumference (AC) measurements in order to select patients for insulin treatment of gestational diabetes mellitus (GDM) with fasting hyperglycemia.
RESEARCH DESIGN AND METHODS-In a pilot study, 98 women with fasting plasma glucose (FPG) concentrations of 105-120 mg/dl were randomized. The standard group received insulin treatment. The experimental group received insulin if the AC, measured monthly, was Ն70th percentile and/or if any venous FPG measurement was Ͼ120 mg/dl. Power was projected to detect a 250-g difference in birth weights.RESULTS -Gestational ages, maternal glycemia, and AC percentiles were similar at randomization. After initiation of protocol, venous FPG (P ϭ 0.003) and capillary blood glucose levels (P ϭ 0.049) were significantly lower in the standard group. Birth weights (3,271 Ϯ 458 vs. 3,369 Ϯ 461 g), frequencies of birth weights Ͼ90th percentile (6.3 vs 8.3%), and neonatal morbidity (25 vs. 25%) did not differ significantly between the standard and experimental groups, respectively. The cesarean delivery rate was significantly lower (14.6 vs. 33.3%, P ϭ 0.03) in the standard group; this difference was not explained by birth weights. In the experimental group, infants of women who did not receive insulin had lower birth weights than infants of mothers treated with insulin (3,180 Ϯ 425 vs. 3,482 Ϯ 451 g, P ϭ 0.03).CONCLUSIONS -In women with GDM and fasting hyperglycemia, glucose plus fetal AC measurements identified pregnancies at low risk for macrosomia and resulted in the avoidance of insulin therapy in 38% of patients without increasing rates of neonatal morbidity.
Diabetes Care 24:1904 -1910, 2001G estational diabetes mellitus (GDM) has been linked to a variety of perinatal complications, the most common being fetal hyperinsulinism and accelerated fetal growth (1-3). Because maternal glucose levels have been directly correlated with risk of accelerated fetal growth and neonatal morbidity (3-6), recommendations for the medical management of women with GDM have focused on prevention of perinatal complications by maintaining pre-and postmeal blood glucose concentrations in a low-risk range in all patients (7). The approach of achieving strict glycemia to eliminate excess macrosomia has, in some studies (5,8), resulted in the requirment of insulin therapy for the majority of patients. However, because only a minority of infants are at risk for perinatal complications in pregnancies complicated by GDM (3-6,9 -11), normalizing glucose levels in all patients may result in unnecessary use of insulin treatment in many pregnancies not at risk for fetal complications; in some cases, this may lead to intrauterine growth restriction (5).In a previous study (12), we used a single measurement of the fetal abdominal circumference (AC) early in the third trimester to identify a large proportion of pregnancies at low risk for neonatal macrosomia when maternal fasting p...
