Predictors of Failed Pelvic Arterial Embolization for Severe Postpartum Hemorrhage

OBJECTIVES: To estimate what factors are associated with a failed pelvic arterial embolization for postpartum hemorrhage and to attempt to estimate efficacy of pelvic arterial embolization in rare conditions. METHODS: This was a retrospective cohort study including all consecutive women who underwent pelvic arterial embolization trial for postpartum hemorrhage between 1994 and 2007 at a tertiary care center. Pelvic arterial embolization failure was defined as the requirement for subsequent surgical procedure to control postpartum hemorrhage. RESULTS: Pelvic arterial embolization was attempted in 0.3% of deliveries by the same radiologist in 87% of cases. Failures occurred in 11 of 100 cases (11%) and in 4 of 17 cases (24%) of placenta accreta or percreta. The major complication rate after pelvic arterial embolization was low (3%). Fifty patients (50%) were transferred from nine other institutions. Pelvic arterial embolization was performed in 11 cases (11%) after a failed conservative surgical procedure and in eight cases (8%) for secondary postpartum hemorrhage, with success rates of 91% and 88%, respectively. Pelvic arterial embolization demonstrated a patency throughout one ligated pedicle in 9 of the 11 cases of failed conservative surgical procedure (82%). Twin pregnancy, chorioamnionitis, operative vaginal delivery, hospital-to-hospital transfer, nature of embolizing agent and arteries embolized, failed surgical procedure, secondary postpartum hemorrhage, cause of postpartum hemorrhage, and more than one pelvic arterial embolization were not found to be significantly associated with failed pelvic arterial embolization. CONCLUSION: The only factors significantly associated with failed pelvic arterial embolization were a higher rate of estimated blood loss (more than 1,500 mL) and more than 5 transfused red blood cell units. Attempted pelvic arterial embolization after a failed vessel ligation procedure and for a secondary postpartum hemorrhage is a good option with high success rates.