Objective To study the effect of carbetocin on intraoperative blood loss and thickness of myometrium during cesarean section with the scarred uterus at term pregnancy. Methods Pregnant women with full-term gestational scar uterus who underwent cesarean section from March 1, 2021, to April 30, 2022, were retrospectively collected and divided into a reference group (using oxytocin) or a study group (using carbetocin). The clinical data of the two groups were retrospectively analyzed, and the operation time, intraoperative blood loss, hospital stay, uterine contraction effect, changes in the myometrium, and complications were compared between the two groups. Results A total of 103 pregnant women were retrieved. There were 44 cases in the reference group and 59 cases in the study group. There were significant differences in operation time, intraoperative bleeding, hospital stay, postoperative adverse events, uterine fundus wall thickness, anterior wall thickness, posterior wall thickness, and uterine contraction effect between the two groups ( p =0.0001, 0.005, 0.006, 0.001, 0.0004, 0.003, 0.001, and 0.005, respectively). There were no significant differences in estradiol (E2), luteinizing hormone (LH), or follicle-stimulating hormone (FSH) between the two groups before the surgery ( p =0.596, 0.840, and 0.940, respectively), but there were significant differences after the surgery ( p =0.011, 0.001, and 0.005, respectively). Conclusion The use of carbetocin in the cesarean section of a full-term scar uterus is significantly effective in shortening the operation time, reducing the amount of intraoperative blood loss, and promoting the recovery of the uterus.