Accuracy of sonographic lower segment thickness and prediction of vaginal birth after caesarean in a resourced‐limited setting; Prospective study

Objectives To assess the accuracy of ultrasound measurement of the lower uterine segment (LUS) thickness against findings at laparotomy, and to investigate its correlation with the success rate of vaginal birth after one previous caesarean delivery (CD) in a resource‐limited setting. Design Prospective study. Setting Obstetrics and Gynaecology department in a tertiary hospital in Ghana. Population Women with one previous CD undergoing either a trial of labour (TOLAC) or elective CD. Methods Myometrial lower uterine segment thickness (mLUS) and full lower uterine segment thickness (fLUS) were measured with transvaginal ultrasound (TVUS). The women were managed according to local protocols with the clinicians blinded to the ultrasound measurements. The LUS was measured intraoperatively for comparison with ultrasound measurements. Main outcome measures Lower uterine segment findings at laparotomy, successful vaginal birth. Results A total of 311 pregnant women with one previous CD were enrolled; 147 women underwent elective CD and 164 women underwent a TOLAC. Of the women that underwent TOLAC, 96 (58.5%) women had a successful vaginal birth. The mLUS was comparable to the intraoperative measurement in the elective CD group with LUS thickness