Significantly enlarged varix in the free-loop of the umbilical cord during the second trimester

Abstract

Abstract Objectives Umbilical cord varix is an abnormal dilatation of the umbilical vein. There are two types of umbilical venous varix, of which the free-loop type is extremely rare, and the prognosis and etiology are unclear. In this report, we present a case of a significantly enlarged varix in the free loop of the umbilical cord found in the second trimester. Case presentation Cesarean section was performed at 28 weeks’ gestation due to enlargement of the varix and rapidly increased umbilical venous velocity at the outlet of the varix. Neonatal blood tests revealed anemia and high concentrations of D-dimer, and they were considered to be due to clot formation inside the umbilical cord venous varix. The neonate received blood transfusion but other neonatal course was generally favorable. Thrombus formation in the enlarged varix was due to the constriction of the umbilical cord. Conclusions This case showed that the assessment of umbilical venous flow velocity can be used for estimating the constriction of the umbilical vein and for determining the timing of delivery.