The objective of the current study was to determine the value of fetal Doppler indices named middle cerebral artery (MCA)-PI, umbilical artery (UA)-PI and cerebro-placental ratio in pregnancies after 42 weeks gestational age and their correlation with the mode of delivery and perinatal outcome. This prospective, observational, clinical study was carried out on 150 women whose gestational age (GA) after 42 weeks' gestation from the first day of last normal menstrual period confirmed by early ultrasound examination during the first trimester attending the antenatal clinic of Benha University Hospital CerebroPlacenta Ratio with cutoff point 1.09 had the best specificity &Middle Cerebral Artery Pulsatily Index with cutoff point = 1.01 had the best sensitivity in prediction af adverse perinatal outcome in prolonged pregnancy . Cerebro-placental ratio shows a highest specificity (93.76%) %) in comparison with middle cerebral artery and umbilical artery pulsatility indices( MCA-PI , UA-PI), so it may be a good test to reassure the obstetricians of the fetal wellbeing.