Ultrasound Prediction of POPP in Active Labor

Persistent occiput posterior position (POPP) represents a relevant risk factor for various adverse outcomes: prolonged labor, higher incidence of operative delivery and/or cesarean section for non-reassuring fetal conditions, higher incidence of high-grade perineal tears (OASIS). For such reasons, labor with POPP needs particular and non-routinary attention. Hence, it is important to diagnose in advance fetuses who present POPP to assure more adequate assistance in labor. Furthermore, digital examination shows a lower detection rate for such condition if compared to ultrasound in labor. This multicenter prospective cross-sectional interventional study aims to evaluate the occiput position and the descent of the fetal head at the beginning of active labor to predict POPP at delivery. All the participants will be subjected to transabdominal and transperineal ultrasound at the beginning of active labor (between 3 and 8 cm of cervical dilatation) to evaluate the position of the fetal head and its descent. At the delivery, the position of the fetal head and the features of the second stage of the labor will be recorded.