Intrauterine life may be a critical period for the programming of later obesity, but there is conflicting evidence about whether pregnancy weight gain is an important determinant of offspring adiposity.
The purpose of this study was to examine the relationship of pregnancy weight gain with neonatal and childhood body composition.
The participants (n=948) were children born to women in the Southampton Women’s Survey who had dual-energy x-ray absorptiometry measurements of body composition at birth, 4 or 6 years. Pregnancy weight gain was derived from the mothers’ measured weights before pregnancy and at 34 weeks gestation, analyzed using 2009 Institute of Medicine (IOM) categories (inadequate, adequate or excessive), and as a continuous measure.
Almost half (49%) the children were born to women who gained excessive weight in pregnancy. In comparison with children born to women with adequate weight gain, they had a greater fat mass in the neonatal period (0.17 SD (95% CI 0.02, 0.32), P=0.03), at 4 years (0.17 SD (0.00, 0.34), P=0.05) and at 6 years (0.30 SD (0.11, 0.49), P=0.002). Greater pregnancy weight gain, as a continuous measure, was associated with greater neonatal fat mass (0.10 SD per 5kg weight gain (0.04, 0.15), P=0.0004) and, weakly, with fat mass at 6 years (0.07 SD per 5kg (0.00, 0.14), P=0.05), but not at 4 years (0.02 SD per 5kg (−0.04, 0.08), P=0.55).
Appropriate pregnancy weight gain, as defined by 2009 IOM recommendations, is linked to lower levels of adiposity in the offspring.