Publications

BACKGROUND: Existing gestational weight gain (GWG) charts vary considerably in their choice of exclusion/inclusion criteria, and it is unclear to what extent  these criteria create differences in the charts' percentile values. OBJECTIVES:  We aimed to establish the impact of including/excluding pregnancies with adverse  neonatal outcomes when constructing GWG charts. METHODS: This is an individual  participant data analysis from 31 studies from low- and middle-income countries.  We created a dataset that included all participants and a dataset restricted to  those with no adverse neonatal outcomes: preterm < 37 wk, small or large for  gestational age, low birth weight < 2500 g, or macrosomia > 4000 g. Quantile  regression models were used to create GWG curves from 9 to 40 wk, stratified by  prepregnancy BMI, in each dataset. RESULTS: The dataset without the exclusion  criteria applied included 14,685 individuals with normal weight and 4831 with  overweight. After removing adverse neonatal outcomes, 10,479 individuals with  normal weight and 3466 individuals with overweight remained. GWG distributions at  13, 27, and 40 wk were virtually identical between the datasets with and without  the exclusion criteria, except at 40 wk for normal weight and 27 wk for  overweight. For the 10th and 90th percentiles, the differences between the  estimated GWG were larger for overweight (∼1.5 kg) compared with normal weight  (<1 kg). Removal of adverse neonatal outcomes had minimal impact on GWG  trajectories of normal weight. For overweight, the percentiles estimated in the  dataset without the criteria were slightly higher than those in the dataset with  the criteria applied. Nevertheless, differences were <1 kg and virtually  nonexistent at the end of pregnancy. CONCLUSIONS: Removing pregnancies with  adverse neonatal outcomes has little or no influence on the GWG trajectories of  individuals with normal and overweight.