Disproportionate alterations in body composition of large for gestational age neonates

Objective: The objective was to compare dual-energy x-ray absorptiometry-measured body composition between large (LGA) and appropriate (AGA) birth weight for gestational age neonates. Study design: LGA term infants (n = 47) with birth weights greater than or equal to 4000 g were compared with 47 gestational age-matched AGA infants; 11 LGA infants were born to mothers with gestational (9) or pregestational diabetes (2). Dual-energy x-ray absorptiometry scans were performed at 1.8 +/- 1.0 days after birth. Results: Body weight and length were the dominant predictors of body composition in LGA and ACA neonates. Howel er, LGA neonates had significantly (P < .001, all comparisons) higher absolute amounts of total body fat, lean body mass, and bone mineral content and had significantly (P < .001, all comparisons) higher proportions of total body fat and bone mineral content but lower lean body mass as a percent of body weight. The changes for total body fat and lean body mass as a percent of body weight were greatest (P < .001) in LGA infants whose mothers had impaired glucose tolerance. Conclusion: LGA neonates have higher body fat and lower lean body mass than AGA infants. Impaired maternal glucose tolerance exaggerated these body composition changes.