Hypovolemic shock at birth due to extensive fetomaternal hemorrhage.

: Three cases are described in which fetomaternal hemorrhage caused hypovolemic shock at birth. The etiology was confirmed by a postpartum maternal smear which showed approximately 15% of fetal red cells in the maternal circulation. All infants had severe anemia with hematocrit values of from 11 to 15%. Initial resuscitative measures included cardiac massage and artificial ventilation. Plasma expanders were given in order to restore the effective circulatory volume. Repeated blood transfusions resulted in an increase of blood pressure to normal range in all patients. One infant survived without neurological sequelae. The other two infants died following irreversible hypoxic injuries to vital organs. Early recognition of perinatal posthemorrhagic shock is crucial for recovery, and whole blood and plasma expander transfusions should be used immediately. Early assisted ventilation, administration of type O- whole blood and the autotransfusion of fetal blood are suggested for restoring the effective circulatory volume.