Macrosomia does not predict overweight in late adolescence in infants of diabetic mothers

Objective. To determine the predictive value of macrosomia for overweight later in adult life in infants of diabetic mothers. Design. Data from the computerized records of the Jerusalem Perinatal Study were matched to measurements made at age 17 obtained from the military draft medical examination records. Participants. 10,891 infants born in Jerusalem between November 1974 and February 1976. Main outcome measures. Macrosomia based on 90th percentile birth weight for gestational age and overweight defined as the 90th percentile for body mass index at age 17. Results. Diabetes was diagnosed in 87 (0.8%) of the mothers. Thirty-one (35.6%) of the infants of the diabetic mothers were macrosomic compared to 1012 (9.4%) of the siblings of nondiabetic mothers (p < 0.001). At 17 years of age 10.3% vs. 9.4% of the siblings of diabetic vs. nondiabetic mothers were overweight (p > 0.05). The rate of adolescent overweight in macrosomic vs. nonmacrosomic subjects was 12.3% vs. 9.7% (p < 0.01) in siblings of nondiabetic mothers, and 16.1% vs. 7.1% (p > 0.05) for diabetic mothers. The sensitivity and specificity, in diabetic mothers, of macrosomia for overweight at age 17 was 44.4% and 66.7%, respectively. The positive and negative predictive value of macrosomia for overweight at age 17 was 16.1% and 92.9%, respectively. Conclusions. The risk of adolescent overweight was significantly increased among macrosomic infants, although this trend did not reach statistical significance in the smaller group of infants born to diabetic mothers. Macrosomia among infants of diabetic mothers had little predictive value for overweight in late adolescence.