Investigators aimed to determine the progression of the descent angle and head symphysis distance measured by intrapartum transperineal ultrasound as an alternative to vaginal examination and bishop score, according to time and cervical dilatation and to draw a sonopartograph as a new indicator also aimed to evaluate the success of the use of transperineal ultrasound in the active phase of labor in predicting prolonged labor, duration and mode of of delivery.

Descent angle and head symphysis distances by transperineal ultrasound of pregnant women who are in the active phase of labor was measured hourly in the first phase of the active phase (the period from 4 cm to full dilation of the cervical opening); every 15 minutes in the second phase of the active phase (time from full dilation to delivery of the baby) Cervical dilatation and head levels were noted by simultaneous digital vaginal examination. The physician who performed the imaging and the physician who made the vajinal examination worked independently of each other and did not see each other's results.

Inclusion Criteria:

• multiparous pregnancy
• active phase in labor
• vertex position

Exclusion Criteria:

• multiple pregnancy
• BMI over 35
• preterm labor
• congenital anomalies