Prediction of vaginal birth after cesarean in China

Objective This study aimed to develop and validate a prediction model of vaginal birth after cesarean delivery (VBAC) in China. Methods A nomogram for effective prediction of VBAC of singleton, cephalic and one previous low‐transverse cesarean section deliveries was created by comparing the combinations of ultrasonographic and non‐ultrasonographic factors from five hospitals between 2018 and 2019. Results A total of 1066 women were included. Of the women who underwent trial of labor after cesarean (TOLAC), 854 (80.1%) had a VBAC. Ultrasound factors included reached a higher area under the curve (AUC) combined with non‐ultrasonographic factors. Of the three ultrasonographic factors analyzed, the best predictive factor for successful TOLAC was fetal abdominal circumference. A nomogram was generated with eight validated factors, including maternal age, gestational week, height, previous vaginal delivery, Bishop score, dilatation of the cervix at the time of admission, body mass index at delivery, and fetal abdominal circumference by ultrasound. The trained and validated AUC were 0.719 (95% confident interval 0.674–0.764) and 0.774 (95% confident interval 0.712–0.837), respectively. Conclusion Our VBAC nomogram based on obstetric factors and fetal abdominal circumference obtained by ultrasound could be used to counsel women who are considering TOLAC. Synopsis Our VBAC nomogram based on obstetric factors and fetal abdominal circumference determined by ultrasound could be used to counsel women who are considering TOLAC.