Objective：This study aims to explore maternal factors and pregnancy related factors affecting intrauterine growth in mid and late pregnancy. Methods：We collected ultrasound data and maternal and health-related information during pregnancy of women who received antenatal examination and delivered in the Women’s Hospital of Nanjing Medical University. A total of 1 457 singleton live birth whose mother had pregnancies of at least 20 gestational weeks between August 2016 and May 2019 and received ultrasound examinations at 22-24，30-32 and 34-36 gestational weeks. Estimated fetal weight（EFW） was calculated based on head circumference（HC），abdomen circumference（AC） and femur length（FL） measured by ultrasound，and and the related factors of intrauterine growth in the middle and late pregnancy were analyzed by mixed linear model. Results：In multivariate analysis，maternal age was positively correlated with EFW at 22-24，30-32 and 34-36 gestational weeks. Compared with mothers with normal pre-pregnancy BMI（18.5 kg/m2≤BMI<24 kg/m2），mothers with underweight（BMI<18.5 kg/m2）had smaller fetuses，and mothers with pregestational overweight/obesity（BMI>24 kg/m2）have larger fetuses at 30-32 and 34-36 gestational weeks. EFW of girls was significantly smaller than that of boys at 22-24，30-32 and 34-36 weeks of gestation. Moreover，We found that pre-pregnancy dysmenorrhea was significantly negatively correlated with EFW during pregnancy. Conclusion：Maternal age，pre-pregnancy BMI，fetal sex and dysmenorrhea may affect estimated fetal weight.