A twin pregnancy is described in which an umbilical cord hemangioma, polyhydramnios, developmental abnormalities and perinatal death were restricted to one twin, while the other twin was unaffected. Cord hemangiomas are rare and their association with fetal abnormalities is controversial. This case study supports a direct association between the cord hemangioma and the adverse pregnancy outcome, since congenital abnormalities and a cord hemangioma were present in only one of the twins.