Erythroblastosis Fetalis

ERYTHROBLASTOSIS fetalis is a disease of the fetus and of the newborn caused by blood-group incompatibility between child and mother. Though there are many different blood groups, the most important incompatibility occurs when the fetus has the Rh blood-group factor on its red corpuscles but the mother lacks it. In the language of the laboratory, such a fetus is Rh-positive because its red cells are agglutinated by anti-Rh typing reagent, and the mother is Rh-negative because her red cells are not affected by the Rh typing serum. If these fetal red cells cross the placental barrier into the circulation of . . .