Abstract:Objective To analyze the feasibility of vaginal delivery in the second pregnancy of scar uterus after cesarean section. Methods A retrospective analysis was performed on the clinical data of 500 second-pregnant women with scar uterus after cesarean section preparing for vaginal trial delivery in Tangshan Maternal and Child Health Hospital from March 2017 to October 2021. According to different modes of delivery, they were divided into cesarean section group（n=348） and vaginal delivery group（n=152）. The general situation and pregnancy outcome of the parturients were observed and compared between two groups, and the factors affecting the smooth vaginal delivery were analyzed. Results There were significant differences in BMI, scar thickness, time interval between two delivery, and the rates of premature rupture of membranes and amniotic fluid contamination between two groups（P＜0.01）. Compared with those in cesarean section group, intrapartum bleeding, postpartum hemorrhage in 24 h, neonatal weight and hospital stay statistically decreased in vaginal delivery group（P＜0.01）. Logistic regression analysis showed that BMI≥30, amniotic fluid contamination and high neonatal weight were the influencing factors of the failure of vaginal trial delivery（P＜0.01）. Large scar thickness was the success factor of vaginal trial delivery（P＜0.05）. Conclusion For the parturients with uterine scar after cesarean section, transvaginal natural childbirth can reduce maternal blood loss without increasing the risk of neonatal 〖JP2〗asphyxia. However, more attentions should be paid to the influence of BMI≥30, amniotic fluid contamination, and neonatal weight on the failure of vaginal trial production, and the vaginal delivery indications should be strictly controlled.