the role of lower uterine segment thickness in predicting cesarean scar defects: two-dimensional transvaginal ultrasound vs. intraoperative findings

Background & objective: to evaluate the risk of uterine rupture during pregnancy, researchers use two-dimensional (2d) transvaginal ultrasound to assess lower uterine segment (lus) thickness in the third trimester of pregnancy. this study aimed to compare the thickness of the lus provided in a 2d transvaginal ultrasound with the findings during a cesarean section (c/s) of pregnant women with a history of previous c/s.materials & methods: this cross-sectional study was performed on 40 pregnant women referred to izadi obstetrics and gynecology hospital in qom. all the women underwent transvaginal ultrasound followed by c/s within a maximum of one week later. also, an expert gynecologist classified lus thickness into four grades in the operation room. results: the mean age of women was 31.58 ± 4.56 years, and the mean thickness of the lus was 2.17 ± 0.51 cm. moreover, 57.5% of the women have graded i of lus based on intraoperative findings. results indicated that the mean thickness of the lus measured by ultrasound significantly differed between the three grades detected by the gynecologist (p=0.04). however, there were no significant differences between maternal age, gestational age, parity, and time of last c/s among women with different lus grades (p˃0.05). transvaginal ultrasound could be helpful in evaluating the risk of scar dehiscence and uterine rupture among women with lus grades i and ii with a history of previous c/s. conclusion: transvaginal ultrasonography, lower uterine segment thickness, cesarean section.