We present a case of extrahepatic umbilical vein varix with mural thrombus.

Our sonography at 31 and 34 weeks of pregnancy revealed a cord varix, complicated with thrombosis at 34 weeks. The thrombus can be seen within the lumen as slightly echogenic, centrally-located mass, spinning as the blood flows peripherally. Color Doppler with appropriate PRF setting (pulse repetition frequency), demonstrates the blood flowing on the sides of the thrombus. We feared for fetal demise within the next hours, should the thrombus become occlusive or generate emboli in the blood stream. Therefore, we performed an emergency C-section at 34 weeks, giving birth to a healthy newborn.

Cord varix is a rare condition characterized by focal dilation of the umbilical vein that can occur in the intrahepatic portion of the vein or in an extrahepatic location. The prognosis is slightly worse if cord varix is identified early in pregnancy or if there are associated fetal anomalies. Although most cases have a favorable outcome, fetal death is attributed to formation of a thrombus in the dilated segment of the vein that blocks fetal venous circulation. A fetus with cord varix should be monitored with serial ultrasound examinations from diagnosis to delivery. If other fetal anomalies are detected, fetal karyotyping should be considered to diagnose or exclude aneuploidy. Fetal echocardiography usually is indicated as cord varix is associated with fetal cardiac abnormalities.