Sonohysterography is a useful diagnostic approach for uterine arteriovenous malformation.

Uterine arteriovenous malformation (AVM) is a rare cause of abnormal uterine bleeding; nevertheless, it is a potentially life-threatening condition when the diagnosis is not made. We report a case of uterine AVM with a secondary uterine hematoma diagnosed 2 weeks after curettage due to spontaneous abortion. Ultrasound examination revealed a mixed echogenic mass of approximately 4 cm × 1.5 cm with no blood flow and an additional contiguous heterogeneous mass with turbulent blood flow depicted by color Doppler. Transvaginal sonohysterography enabled us to exclude residual chorionic tissues and to make precise diagnosis of uterine AVM with a secondary hematoma.