总结妊娠相关子宫假性动脉瘤的超声表现及临床特征，探讨其发病机理。

回顾性收集2016年1月至2020年12月于首都医科大学附属北京妇产医院就诊的妊娠相关子宫假性动脉瘤患者21例，对其超声图像及临床特征进行归纳分析。

21例患者原发病包括滋养细胞肿瘤7例、瘢痕妊娠2例、早孕期胚物残留10例、胎盘残留或植入2例。19例患者血hCG异常增高，中位数2573.30（60.00，12001.30）IU/L。18例经病变局灶切除或全子宫切除获得病理，均于子宫假性动脉瘤处见不同程度退变的绒毛或滋养细胞。所有患者超声表现均符合假性动脉瘤特征，可探及破裂载瘤动脉血液直接流入假腔，裂口处频谱呈高速低阻。8例累及放射动脉、13例累及弓形动脉。

绒毛或滋养细胞对子宫肌层的侵蚀是妊娠相关子宫假性动脉瘤发生的重要致病因素，超声检查对子宫假性动脉瘤诊断及疗效评估有重要价值。

To summarize the ultrasonographic features and clinical characteristics of pregnancy associated uterine artery pseudoaneurysms (UAPs), and to explore their pathogenesis.

Ultrasound images and clinical data of 21 patients with pregnancy associated UAPs admitted to our hospital from January 2016 to December 2020 were collected and analyzed.

The primary diseases included seven cases of trophoblastic tumor, two cases of cesarean section scar pregnancy, ten cases of embryo residue in early pregnancy, and two cases of placenta residue or implantation. Blood human choionic gonadotophin was found abnormally increased in 19 patients, with a median of 2573.30 (60.001, 2001.30) IU/L. Pathologic examination of 18 patients revealed degenerated villi or trophoblasts. The ultrasound findings were consistent with the characteristics of pseudoaneurysm; the feeding vessels were damaged and the blood flow leaked into the false cavity directly. Pulse Doppler revealed an arterial blood flow spectrum with high speed and low resistance index. In eight patients, the radial arteries were involved, and in the other 13 patients, the arcuate arteries were involved.

Invasion of the myometrium by villi or trophoblasts is an important pathogenic factor for pregnancy associated UAPs. Color Doppler ultrasound has significant importance in the diagnosis of pregnancy associated UAPs and in monitoring the efficacy of therapy in such patients.