Gestational weight gain and overweight in children: Results from the cross-sectional German KiGGS study.

Abstract Objective. Gestational weight gain (GWG) has been associated with overweight in offspring. The aim of the study was to assess the association of GWG with childhood overweight and a potential effect modification by maternal BMI. Methods. In a cross-sectional study of 10 784 children aged 3 to 17 years from the German national child health survey (2003-2006), main outcome measure was overweight defined by the criteria of the International Obesity Task Force. Main exposure was GWG in data-derived categories. Results. Crude and adjusted odds ratios (OR) for high and low GWG with average GWG as a reference were calculated in logistic regression models. With adjustment for potential confounders, the OR of childhood overweight for high GWG was 1.16 (95% confidence interval [CI]: 1.02, 1.32), whereas for low GWG the adjusted OR was not significant at 1.01 (95% CI: 0.89, 1.15). Stratified analyses by estimated pre-pregnancy BMI revealed inconsistent effects of high GWG on childhood overweight, with a significantly increased risk for children of normal-weight mothers only. No statistically significant advantageous effect of low GWG was present for any of the maternal BMI subgroups. Conclusion. A high compared with an average GWG accounts for a moderate increase in the risk of offspring overweight, whereas a lower than average GWG does not appear to reduce this risk. Subgroup analyses suggested that the beneficial effect of avoidance of high GWG might be confined to normal-weight mothers. Interventions promoting healthy GWG should not only target overweight and obese, but also normal-weight females.