Giant Uterine Fibroid with Vascular Pseudocyst and Intrauterine Rupture: A Rare Life- Threatening Emergency

Background Uterine fibroids are common benign tumors, yet their potential for life-threatening vascular complications is exceedingly rare. This report details an exceptional case of hemorrhagic shock caused by a ruptured vascular pseudocyst (pseudoaneurysm) arising from the stalk of a giant pedunculated uterine fibroid. Case Presentation A 45-year-old premenopausal woman presented with painless vaginal bleeding culminating in hemorrhagic shock (hemoglobin 57 g/L). Pelvic imaging revealed a 25 cm pedunculated fibroid originating from the lower uterine segment. Computed tomography angiography (CTA) identified a critical finding: a 2.0 × 1.5 cm vascular pseudocyst at the stalk base, supplied by aberrant hypertrophied uterine arteries and showing evidence of rupture. Emergency hysterectomy confirmed a bleeding pseudoaneurysm at the fibroid's peduncle. Histopathology confirmed a benign, degenerated leiomyoma and a pseudoaneurysmal cavity devoid of endothelial lining, consistent with a vascular pseudocyst. Conclusion This case illustrates that large pedunculated uterine fibroids, while typically benign, can rarely develop stalk-based vascular pseudocysts (pseudoaneurysms) leading to catastrophic hemorrhage. In patients presenting with a pedunculated pelvic mass and acute symptoms, prompt CTA evaluation for vascular anomalies is crucial. Early recognition and immediate surgical or interventional radiological management are vital to prevent life-threatening outcomes.