The uterine arteries are the main blood vessels that supply blood to the uterus. They give off branches that supply different portions of the uterus and play an important role in maintaining blood supply during physiological processes, such as the altering endometrium during the menstrual cycle and growth of the uterus during pregnancy. During its course, the uterine artery passes anterior to the distal ureter; some refer to this as “water under the bridge. Intrauterine growth restriction (IUGR) is a common and complex obstetric problem. IUGR is noted to affect approximately 10-15 % of pregnant women. IUGR is a diagnosis commonly made antenatally; however, some of these fetuses, especially if unscreened during pregnancy, may be detected only in the newborn period. It is very important for obstetricians and perinatologists to recognize growth restricted fetuses, because this fetal condition is associated with significant perinatal morbidity and mortality. Umbilical artery Doppler studies and antenatal surveillance are very good predictors of pregnancy outcomes in both types of IUGR. Uterine Artery Doppler correlates well with hemodynamic changes in the placental circulation. The aortic isthmus (AoI) is anatomically located between the origin of the left subclavian artery and the aortic end of the ductus arteriosus (DA). The AoI can be viewed using either of two sonographic planes. These are the traditional longitudinal aortic arch (LAA) view, where the sonographic gate is placed a few millimeters beyond the origin of the left subclavian artery, and the crosssectional three vessels and trachea (3VT) view, where the sonographic gate is placed just prior to the convergence of the AoI on the DA. Theoretically, if cerebral vascular impedance were to decrease, a higher proportion of the LV stroke volume would be redistributed to the brain, reducing the influence that the LV has upon the AoI systolic component in comparison to the RV. Concomitantly, there would be an increase in right ventricular preload. Thus, it is unlikely that in conditions such as IUGR the ISI would selectively be quantifying only comparative ventricular contribution to CO

Fetus, Intra Uterine Growth Restriction, Aortic Isthmus Doppler