We report 22 cases of hepatic necrosis following catheterization of the umbilical vein. The morphology of the necrotic lesions, which were confined to the left lobe in 21 patients, was that of an anemic infarct. Their causes are multiple and include intimal damage during the insertion of the catheter with consecutive thrombosis of portal vein branches, the postpartum immaturity of the arterial hepatic oxygen supply, postpartum hypoxia due to respiratory failure of cerebral or pulmonary origin, obstruction of portal venous flow through the catheter as such, the postpartum involution of the left hepatic lobe, and prolonged periods of catheterization. Toxic damage of the hepatic parenchyma due to an infusion of Tris buffer through the catheter into the portal venous system is a potential additional factor.