Abstract: Objective:To investigate the epidemic situation of the macrosomia in Minhang area of Shanghai,and analyze its influencing factors.Methods:The neonates from two hospitals in Minhang area of Shanghai were investigated from 2013 to 2015,and the 1 963 macrosomias and 5 889 nonmacrosomias selected by casting coin at the same time were divided into the obseravtion group and control group,respectively.The prenatal general situation,mode of delivery and complications between two groups were compared.Results:The mother with gestational diabetes mellitus,gestational overweight,prepregnancy BMI overhigh and diet control during pregnancy were the high risk factors of macrosomia(P<0.01).The rates of cesarean section,intrapartum asphyxia,and the incidence rates of neonatal jaundice and congenital heart disease of macrosomias in observation group were significantly higher than those in control group(P<0.01).Conclusions:The prenatal diagnosis and management of macrosomia should be paid attention to.Selecting the appropriate mode of delivery can improve the pregnancy outcome.