Uterine arteriovenous malformation (UAVM) as a rare cause of postpartum hemorrhage (PPH): a literature review

Purpose: Uterine arteriovenous malformations (UAVM) are rare vascular lesions characterized by an abnormal arteriovenous communication between the branches of uterine artery and the myometrial venous plexus. UAVM can be a serious cause of massive post-partum hemorrhage (PPH) leading to potentially life-threatening anemic shock. This review aims to summarize main experiences on clinical presentation and management of UAVM in the setting of unexplained PPH.

Methods: A systematic review of the literature in Scopus, PubMed and MEDLINE was conducted. A case report of a PPH UAVM-related in a patient managed at the authors' center is also provided.

Results: Eleven studies met the inclusion criteria. The mean age of cases was 30. In 3/11 cases, previous uterine surgeries were reported and 72.7% cases gave birth by cesarean section. Nine cases had a secondary PPH (24 h up to 12 week post-partum), whereas only one case had a primary PPH. Our case report had both a primary and a secondary PPH. Reported vaginal bleedings were profuse and blood loss entity ranged from 1000 to 2000 ml. In all cases a color Doppler ultrasound was performed first to suspect UAVM and in 10/11 cases a subsequent pelvic angiography confirmed the diagnosis of UAVM as leading cause of the unexplained PPH. In 81.8% cases a conservative management by uterine artery embolization (UAE) was adopted: bilateral UAE was always successful; in 1 out of 2 cases treated by unilateral UEA, emergency total hysterectomy was performed for a sudden hemodynamic instability.

Conclusion: Maternal mortality pregnancy-correlated is a major health concern worldwide, mostly due by PPH. UAVM should be considered in clinical practice among possible causes of unexplained PPH.