Spontaneous development of endometrial venous malformation: diagnosis with color Doppler sonography

We report the case of a spontaneous development of venous malformation within the endometrium of a patient with adenomyosis who was on oral contraceptives for a prolonged period of time. This vascular abnormality was incidentally identified and diagnosed with color Doppler ultrasound when the patient was referred for pelvic ultrasound for her symptoms related to adenomyosis. The vascular abnormality was characterized as venous malformation based on its Doppler tracing. The possible causes of its spontaneous development are discussed.