Difficulty in Diagnosing Cesarean Scar Pregnancy Using Magnetic Resonance Imaging: Importance of Color Doppler Assessment in Treatment Decision-Making

Cesarean scar pregnancy (CSP) is a rare but potentially life-threatening form of ectopic pregnancy, and its diagnosis may be challenging in early pregnancy.We report a case of a 40-year-old woman with a history of one cesarean section who was referred with suspected cervical pregnancy.Transvaginal ultrasonography demonstrated a cystic lesion at the cesarean scar site without detectable blood flow, whereas magnetic resonance imaging (MRI) suggested right adnexal ectopic pregnancy.Laparoscopic surgery was initiated; however, no adnexal pregnancy was identified, and the procedure was converted to ultrasound-guided uterine evacuation without preoperative uterine artery embolization.Chorionic villi were confirmed pathologically, and the postoperative course was uneventful.This case highlights that MRI findings may be atypical in early CSP and that color Doppler ultrasonography of peritrophoblastic blood flow may be useful for treatment planning, including decisions on preoperative uterine artery embolization.