A high-risk pregnancy is one in which the mother or fetus has a significantly increased chance of death or disability. High Risk pregnancy includes: Hypertensive disorders in pregnancy, Diabetes mellitus with pregnancy, postdate, Multifetal pregnancy, Rh isoimunization and IUGR.The objectives of fetal surveillance for high risk patients are to determine the gestational age, fetal congenital anomalies, normal fetal growth and the severity of acute and chronic fetal asphyxia. methods used including: biochemical tests, fetal daily movement count, fetal biophysical profile, middle cerebral and umbilical artery Doppler. The aim of this study is to detect the accuracy of the middle cerebral to umbilical artery resistance index ratio in predicting foetal outcome in cases of high risk pregnancy.