Gestational weight gain and child weight status at 5 years of age: differential effects by prepregnancy body mass index status

Abstract

In 2009, IOM released recommendations for gestational weight gain (GWG) and noted a data gap on associations with long‐term outcomes, specifically child weight. Currently the mediating role of birthweight and heterogeneity by prepregnancy BMI are unclear. We used the nationally representative Early Childhood Longitudinal Study‐Birth Cohort to examine associations between GWG and subsequent child weight measured at 5 y. We used regression and path analysis to examine direct and indirect effects mediated by birthweight. Among underweight, normal, overweight and obese women, respectively, prevalence of excessive GWG (above recommendations) was 26%, 38%, 62% and 53%, and child obesity (BMI ≥ 95th percentile) was 9%, 13%, 19% and 27%. Multivariable logistic regression indicated null associations between inadequate GWG and child obesity for all prepregnancy BMI groups, but a significant association with excessive GWG among only normal [OR 1.8 (95% CI 1.3, 2.5)] and overweight [OR 2.0 (95% CI 1.1, 3.4)] women. Path analysis with child BMI z‐score further indicated that among normal and overweight women the direct effect of GWG was stronger than the indirect effect. Among obese women, there was no significant total effect of GWG. Our findings indicate that IOM GWG recommendations are appropriate in the context of child weight; prevention of excessive GWG may be a strategy to prevent child obesity.Grant Funding Source: Oak Ridge Institute for Science and Education (ORISE)