Doppler blood flow parameters of uteroplacental and fetal vessels (umbilical artery, fetal aorta, fetal common carotid artery) were tested to determine their clinical value in predicting IUGR or fetal hypoxia, considering the time interval from the examination to the delivery. More than 2 weeks before the delivery, only Doppler parameters of uteroplacental vessels revealed a sensitivity of detecting IUGR of above 50%, using the resistance index. In the last two weeks before the delivery, there was a significant increase of the clinical value of fetal blood flow parameters. The sensitivity of the ratio of the mean blood flow velocity of the fetal common carotid artery to the fetal aorta with a view to detecting a pathological CTG was 94% with a specificity of 60%. In summary, we conclude that blood flow parameters of uteroplacental vessels can be used for screening examinations. Blood flow parameters of fetal vessels are indicated for the supervision of risk pregnancies. The redistribution of the fetal circulation is reflected in the ratio of blood flow parameters of the common carotid artery to the umbilical artery or to the fetal aorta. These parameters seem to be helpful for the early detection of imminent fetal hypoxia in cases with risk pregnancy. Even when a suspicious or pathological CTG does not allow an exact diagnosis of fetal hypoxia, this does not change the basic meaning of this study.