We report a case of massive chronic foetomaternal hemorrhage. The labor cou
rse was uncomplicated. The newborn presented with pallor, tachypnea, and mo
derate hepatosplenomegaly. The initial hemoglobin was 6.5 g/dl. The Kleihau
er-Betke stain on a maternal blood sample was 12%, which is equivalent to 5
40 ml of fetal blood in the maternal circulation. A clot in the umbilical v
ein was demonstrated sonographically. The possible association of foetomate
rnal hemorrhage with umbilical vein thrombosis is discussed.