Effect of pre－pregnancy body mass index and gestational weight gain on birth weight of infants: a prospective cohort study / 中华疾病控制杂志

ABSTRACT

@#Objective To analyze the relationship between pre － pregnancy body mass index ( BMI) ，gestational weight gain ( GWG) and the birth weight of infants，and explore the effect of weight change before and during pregnancy on low birth weight ( LBW) and macrosomia． Methods Women were enrolled by the Chinese Pregnant Women Cohort Study during first trimester． Each respondent＇s weight before and during pregnancy and the birth weight of infant were collected after fellow up． Prepregnancy BMI was divided into underweight，normal and overweight /obesity groups and GWG was divided into suitable， insufficient and excessive groups． Multivariate Logistic regression was adopted to explore the relationship be- tween pre－pregnancy BMI，GWG and newborn＇s birth weight． Ｒesults Women＇s prepregnancy BMI and GWG were associated with neonatal birth weight ( all P＜0. 05) ． Prepregnancy overweight or obesity ( OＲ=2. 339，95% CI 1. 674－2. 282，P＜0. 001) and excessive GWG ( OＲ= 1. 398，95% CI 1. 188－1. 978，P= 0. 048) were shown as risk factors for macrosomia． Insufficient GWG increased LBW risk ( OＲ = 1. 479， 95% CI 1. 461－1. 679，P= 0. 035) while excessive GWG declined LBW risk ( OＲ= 0. 428，95% CI 0. 225 －0. 817，P= 0. 010) ． Under weight－insufficient GWG was risk factor of LBW ( OＲ= 1. 335，95% CI 1. 048 －2. 319，P= 0. 048) while normal BMI－excessive GWG ( OＲ= 1. 088，95% CI 1. 016－1. 675，P= 0. 038) and overweight /obesity－excessive GWG ( OＲ= 1. 498，95% CI 1. 244－2. 017，P= 0. 046) were associated with higher risk of delivering macrosomia． Conclusions Prepregnancy BMI and GWG were associated with infant＇s birth weight and women were suggested to maintain their weight in recommended range before and during pregnancy．