Abstract： Objective To investigate the safety and clinical efficacy of uterime artery chemoembolization in postpartum hemorrhage (PPH) caused by abnormal placental implantation.Methods Between December 2006 and September 2009, there were 23 cases of abnormal placental implantation with PPH in our hospital, among which 9 presented with continuous small amount of vaginal bleeding and 14 with acute excessive bleeding.The average bleeding time was (8±6) d and the mean blood loss was (980±660) ml.Abnormal placental implantation was confirmed by color Doppler ultrasound (CD-US) in all cases, the internal lilac artery angiography was performed to identify the uterine artery and bilateral uterine artery chemoembolization (UACE) with methotrexate (MTX) and gelfoam particles to the distal end of uterine artery was conducted after.CD-US rechecked all patients within 48 h after UACE and those patients with blurred margins between placenta and uterus and abnormal blood flow (> 1 cm×1 cm) received ultrasonic-guided per vagina MTX multipoint injections.All cases were followed up for 3-26 months (average 12 months) to observe vaginal bleeding, placenta tissue discharge, serum human chorionic gonadotropin (hCG), uterine involution, menses, and side-effects or complications.Results (1) Curative effect: These 23 cases underwent 24 procedures of UACE successfully and vaginal bleeding ceased at an average of (3.5±1.3) min after UACE.Reduced blood flow in the placental implantation area was detected under CD-US after UACE.Among the 23 patients, wterine curettage was required in 16 cases due to retained placenta tissues with the mean blood loss of (40 ± 28) ml during the operation, 2 underwent subtotal hysterectomy and confirmed to be placenta percreta by pathology examination, and placenta tissues were spontaneously discharged completely in 5 cases.Totally, 91% of the patients (21/23) reserved their uterus.(2) Follow-up: the serum hCG reduced to normal within 1-13 d after the placenta tissue were evacuated.Regular menstruation returned within 2-3 months in those patients who reserved uterus and normal size uterus was found under sonography at 3 months.No severe complication was reported except for some post embolization syndrome, such as pelvic pain or fever.Conclusions UACE, combined with ultrasonic-guided transvaginal MTX injection, is a safe, minimal invasive and quick hemostatic procedure in treatment of abnormal placental implantation with PPH, and allows the preservation of uterus possible.CD-US is helpful in evaluation of the blood flow changes before and after UACE in abnormal placental implantation patients.