- Hemangiomas are benign vascular lesions located mostly in the region of the head and neck w x 1 . The majority are small, and therefore, cannot be diagnosed prenatally, yet in certain cases, they are of a significant size which enables detection w x through ultrasound screening 2 . A 30-year-old woman, gravida 4 para 2 with a normal medical history was referred to our ultrasound unit after a third trimester sonogram. An ultrasound examination revealed a 72=51-mm hypoecogenic mass in the posterior upper part of Ž . the left thigh with a regular contour Fig. 1 . Color Doppler imaging showed a rich, low velocity, arterial flow within the mass. A diagnosis of giant hemangioma of the thigh was made. Repeated ultrasound examinations at 34 and 38 weeks of gestation did not show enlargement of the mass. However, a minimal pericardial effusion with mild tricuspid valve regurgitation was noted at the last examination.