Body composition analysis in infants of diabetic and obese mothers

Background Maternal diabetes and obesity often result in large for gestational age infants. However, the effects of these conditions on infant body composition remain understudied. The purpose of this study was to examine the impact of maternal obesity and gestational diabetes mellitus (GDM) on infant body composition using air displacement plethysmography (ADP) and traditional anthropometric measurements. Relationships between body composition assessment techniques were also explored. Methods A prospective cohort of 50 healthy term infants was enrolled. Infants were assigned to one of three groups: infants of mothers with prepregnancy body mass index (BMI) <30 kg/m 2 and no history of GDM (normal term, n=20), infants of mothers with prepregnancy BMI ≥30 kg/m 2 and no history of GDM (obese mothers, n=18) or infants of mothers with a history of GDM (infants of diabetic mothers, n=12). ADP measurements were performed at birth and 3 months of age. Anthropometric measurements were taken at birth, 3 months and 1 year of age. A subset of infants also underwent dual-energy X-ray absorptiometry (DXA) scan at birth and 3 months of age. Results There were no significant differences in anthropometric or ADP measurements between groups at any timepoint. The change in all measurements over time was also similar between groups. There was a strong linear correlation between DXA and ADP measurements (r=0.9; p=0.001), but poor agreement between the methods (limits of agreement: −27.2% to 9.3%). Arm circumference and body length were most consistently predictive of per cent body fat (selection frequency: 0.93 and 0.79, respectively). Conclusions Maternal history of obesity and/or GDM did not alter infant body composition in our predominantly Hispanic cohort; however, the limited sample size may have reduced our ability to detect modest differences. There was substantial disagreement between DXA and ADP estimated per cent body fat, and these methods should not be used interchangeably. Combinations of anthropometric measurements could be useful for approximating body composition at institutions lacking more sophisticated equipment.