Uterine arteriovenous malformation (AVM) can cause sudden massive hemorrhage. We report a case of uterine AVM following curettage in a patient treated conservatively with an intermediate-dose pill. An 18-year-old gravida 2 para 0 underwent curettage at 12 weeks of gestation and was examined for massive genital hemorrhage that occurred in postoperative month 4. Abundant blood flow in a mass within the uterine lumen was observed on color Doppler ultrasonography, and the patient was diagnosed with AVM. Six days after starting oral norgestrel/ethinyl estradiol, the hemorrhage ceased, and computed tomography on day 37 of administration showed disappearance of the abnormal vasculature. After 12 months, the patient's course remains favorable without relapse. Transarterial embolization for AVM can cause ovarian failure and subsequent placental malpositioning. Administration of oral norgestrel/ethinyl estradiol may be an alternative conservative treatment option for patients who wish to maintain fertility.