The uterine artery is a branch of the internal iliac artery that provides the primary blood supply to the uterus. During pregnancy, the uterine arteries undergo remarkable changes, with their resistance decreasing significantly to allow increased blood flow to the growing uterus and placenta. On Doppler ultrasound, the uterine arteries are evaluated by measuring their pulsatility index (PI) and looking for the presence or absence of an early diastolic notch. Abnormally high resistance in the uterine arteries (elevated PI with persistent notching beyond 24 weeks) is associated with an increased risk of preeclampsia, fetal growth restriction, and other pregnancy complications. Uterine artery Doppler is used as a screening tool in high-risk pregnancies and also has applications in gynecology, including evaluation of fibroid vascularity and before uterine artery embolization procedures.
Sonography Term