Introduction: Uterine rupture occurs in many pregnancies. The risk is higher for women who plan to have a normal birth after a previous cesarean section than for those who have another cesarean section. Objectives: This study aimed to predict the thickness of the lower uterine segment (LUS) by comparing a 2D transvaginal ultrasound with the findings during a cesarean section (C/S) in pregnant women with a history of previous cesarean sections. Methodology: This cross-sectional study was done at the Department of Obstetrics and Gynaecology, at the Institute of Child and Mother Health, Bangladesh from June 2023 to May 2024. A well-structured questionnaire was used for data collection. 100 women underwent transvaginal ultrasound followed by cesarean section (C/S) within a maximum of one week later. Also, an expert gynaecologist classified LUS thickness into four grades in the operation room. Result: The mean age of the women in the study was 30.7 years (±9.62), while the mean thickness of the lower uterine segment (LUS) was 2.25 cm (± 0.55). Among the participants, 43 were classified as grade I for the LUS based on intraoperative findings. The results indicated a significant difference in the mean thickness of the LUS measured by ultrasound across the three grades identified by the gynaecologist (P = 0.04). However, there were no significant differences in maternal age, gestational age, parity, or the time since the last cesarean section among women with different LUS grades (P > 0.05). Transvaginal ultrasound may be useful in assessing the risk of scar dehiscence and uterine rupture in women with LUS grades I and II who have a history of previous cesarean sections. Conclusion: Sonographic lower uterine segment thickness prediction is very important in the study of lower uterine segment thickness after a prior cesarean section to predict uterine rupture. 2D vaginal ultrasonography can be used to assess the risk of uterine scar dehiscence of grades I and II.