Gestational weight gain and the risk of offspring obesity at 10 and 16years: a prospective cohort study in low-income women

ObjectiveTo study the association between gestational weight gain (GWG) and offspring obesity risk at ages chosen to approximate prepuberty (10years) and postpuberty (16years). DesignProspective pregnancy cohort. SettingPittsburgh, PA, USA. SampleLow-income pregnant women (n=514) receiving prenatal care at an obstetric residency clinic and their singleton offspring. MethodsGestational weight gain was classified based on maternal GWG-for-gestational-age Z-score charts and was modelled using flexible spline terms in modified multivariable Poisson regression models. Main outcome measuresObesity at 10 or 16years, defined as body mass index (BMI) Z-scores 95th centile of the 2000 CDC references, based on measured height and weight. ResultsThe prevalence of offspring obesity was 20% at 10years and 22% at 16years. In the overall sample, the risk of offspring obesity at 10 and 16years increased when GWG exceeded a GWG Z-score of 0 SD (equivalent to 30kg at 40weeks); but for gains below a Z-score of 0 SD there was no relationship with child obesity risk. The association between GWG and offspring obesity varied by prepregnancy BMI. Among mothers with a pregravid BMI<25kg/m(2), the risk of offspring obesity increased when GWG Z-score exceeded 0 SD, yet among overweight women (BMI 25kg/m(2)), there was no association between GWG Z-scores and offspring obesity risk. ConclusionsAmong lean women, higher GWG may have lasting effects on offspring obesity risk. Tweetable abstractMaternal weight gain is associated with offspring obesity at 10 and 16years in a prospective study.