Effects of pregestational body mass index and body weight gain during pregnancy on birth weight of neonates

Objective To study the effects of pregestational body mass index(BMI)and weight gain during pregnancy on the birth weight of neonates.Methods 2 976singleton full-term pregnant women were selected for a cohort study.Their prepregnancy height and weight,weight gain during pregnancy as well as neonates' birth weight were collected and analyzed.Results Incidence of macrosomia was 10.18%,which increased as pre-pregnancy body mass index(BMI)or weight gain during pregnancy increased.Neonates of group with overweight before pregnancy or excessive weight gain during pregnancy had the highest maternal birth weights,followed by group with normal weight before pregnancy or appropriate weight gain during pregnancy.Group with low pre-pregnancy weight or insufficient weight gain during pregnancy had the lowest neonates' birth weight.Conclusion The pre-pregnancy body mass index(BMI)and gestational weight gain are crucial factors for neonates' birth weight.It is necessary to strengthen the perinatal maternal weight management and provide nutrition and health guidance during pregnancy to reduce the incidence of macrosomia and improve the quality of prenatal care.