Retained products of conception (RPOC) refer to the persistence of placental or fetal tissue in the uterus following delivery or miscarriage. RPOC may cause massive postpartum or post-abortion hemorrhage. Arterial embolization (AE) is an effective choice of management for postpartum hemorrhage including RPOC. We report a case of hemorrhagic RPOC, in which uterine artery embolization with transcervical resection did not achieve hemostasis, and laparotomy with uterine compression sutures was subsequently required. The RPOC was apparently fed by an aberrant branch derived from the inferior mesenteric artery (IMA). AE of IMA was not performed because of possible necrosis of the descending colon and rectum. A physician should be aware that AE is not an all-encompassing hemostatic technique for postpartum bleeding, such as with RPOC, and should keep alternatives in mind.