Prepregnancy Body Mass Index as a Significant Predictor of Total Gestational Weight Gain and Birth Weight

Abstract

Purpose: We aimed to describe adherence to gestational weight gain (GWG) recommendations and identify determinants of excessive GWG in a sample of women from Quebec, Canada. Methods: Data were collected from the multi-centre 3D (Design, Develop, Discover) pregnancy cohort study, which included women who delivered between May 2010 and August 2012 at 9 obstetrical hospitals in Quebec, Canada. GWG was calculated for 1145 women and compared to the 2009 Institute of Medicine (IOM) recommendations. Results: Overall, 51% of participants exceeded the recommendations. Approximately 68% of women with obesity gained weight in excess of the IOM recommendations. The corresponding numbers were 75%, 44%, and 27% in overweight, normal weight, and underweight women, respectively. A prepregnancy BMI of 25 kg/m2 or more was the only significant predictor of exceeding GWG recommendations (OR 3.35, 95% CI 2.44–4.64) in a multivariate model. Birth weight was positively associated with GWG. GWG and prepregnancy BMI could explain 3.13% and 2.46% of the variance in birth weight, respectively. Conclusion: About half of women exceeded GWG recommendations, and this was correlated with infant birth weight. This reinforces the need to develop and evaluate strategies, including nutritional interventions, for pregnant women to achieve optimal GWG.