在非孕期，子宫动脉血流波形为高阻力低舒张期血流和舒张早期切迹。正常妊娠期，子宫动脉血管阻力从妊娠早期到中期持续降低，妊娠晚期变化不大，大约50%的正常孕妇在早期妊娠结束时子宫动脉仍有舒张早期切迹，几乎在24周消失。子宫动脉血流反映了滋养细胞对螺旋动脉的重塑情况。在并发子痫前期（PE）和（或）胎儿生长受限（FGR）的妊娠中，血流阻力通常降低较少，导致子宫动脉阻力指数（RI）和搏动指数（PI）较正常妊娠增加。子宫动脉血流可用于妊娠早期筛查早发型PE和FGR，但预测价值有待进一步研究。在妊娠中期和晚期，子宫动脉多普勒超声可用于评估FGR，但对异常结果的干预措施并未证明有效。在复发性流产中，依据子宫动脉血流阻力进行治疗并未见有高质量的循证医学证据。

The waveform of uterine artery blood flow is high resistance low diastolic flow and early diastolic notch during non-gestational period. During normal pregnancy，uterine arterial vascular resistance decreases continuously from early to mid-pregnancy，and does not change much in late pregnancy. About 50% of normal pregnant women have an early diastolic notch in the uterine artery at the end of early pregnancy，which almost disappears at 24th gestational week. Uterine artery blood flow reflects the remodeling of spiral arteries by trophoblasts. In pregnancies complicated by preeclampsia（PE）and/or fetal growth restriction（FGR），blood flow resistance is usually less reduced，inducing increased uterine artery RI and PI compared to normal pregnancies. Uterine arterial blood flow can be used in early pregnancy to screen for early-onset PE and FGR，but the predictive value needs further study and it can also be used to assess FGR during second and third trimesters，but interventions for abnormal outcomes have not been proven effective. There is no high-quality evidence-based medical evidence for treatment according to uterine artery flow resistance in recurrent miscarriage.