Conclusion
RA
Overall, the findings suggest that trans-labial ultrasound plays a significant role in the management of labor and helps to make the right decisions in the labor process. As such the Angle of progression (AoP) and Rotation Angle (RA) measured by trans-labial ultrasound were influential factors to predict vaginal birth or cesarean section in labor process. Indeed, further investigations on the use of trans-labial ultrasound for the prediction of successful vaginal birth are recommended.