Excessive weight gain in women with a normal pre-pregnancy BMI is associated with increased neonatal adiposity

Background More than 40% of women with a normal pre-pregnancy body mass index (BMI) exceed the 2009 Institute of Medicine (IOM) guidelines' recommended weight gain of 2535lb. Excessive gestational weight gain is one modifiable factor that may be contributing to childhood overweight and obesity. Objective The objective of this study was to evaluate differences in adiposity from neonates born to mothers with a normal pre-pregnancy BMI who either gained within or above IOM guidelines. Methods Neonatal adiposity was measured within 72h of birth by the method of air displacement plethysmography. Results Compared with mothers who gained within IOM guidelines (N=27), mothers with excessive gestational weight gain (N=11) (mean 29.0 vs. 45.2lb) had neonates with 50% more fat mass (348 vs. 525g) and 3% greater body fat (10.7 vs. 13.9%). Conclusions Increased adiposity at birth may predispose these children to increased risk of obesity and highlight the importance that women avoid gaining excessive weight in pregnancy.