Assessment of maternal and fetal Doppler in low risk term pregnancies in early labour and correlation with obstetric and neonatal outcome.

The identification of intrapartum hypoxia is among the current challenges of the Obstetric practice. Available data have shown that such hypoxic events, despite being rare, most commonly occur in uneventful and apparently low risk pregnancies in appropriately grown fetuses. The antenatal monitoring of fetal wellbeing aims to identify those fetuses at risk of hypoxic events related to labour and delivery and promptly arrange effective interventions in order to prevent adverse perinatal outcomes. Nevertheless, continuous intrapartum monitoring by means of cardiotocography (CTG) has not demonstrated a significant reduction in the incidence of adverse perinatal outcome and has been associated with an increase in the caesarean section rate, particularly among women considered at low risk. Available evidences from the literature suggest that abnormalities in the uterine artery Doppler and in the ratio between fetal cerebral and umbilical Doppler (i.e. cerebroplacental ratio, CPR) are associated with conditions of subclinical placental function occurring in fetuses who have failed to achieve their growth potential, hence at risk of intrapartum complications. The purpose of this study is to prospectively assess maternal and fetal Doppler in early labour in order to evaluate whether abnormalities of the Doppler parameters may identify those fetuses at higher risk of intrapartum distress.