About one baby in 300 is born with erythroblastosis.
Those with more serious cases of erythroblastosis fetalis suffer from the presence in the blood of too many erythroblasts, or immature red blood cells.
From the machine came a startling fact: of 137 infants with erythroblastosis who got the Rh-negative blood of male donors, 27 died; of 42 who got women's blood, not one died.