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erythroblastosis fetalis erythroblastosis fe·ta·lis (fē-tā'lĭs)
A severe hemolytic disease of a fetus or newborn caused by production of maternal antibodies for fetal red blood cells, usually involving Rh incompatibility between the mother and fetus. Also called ABO hemolytic disease of newborn, congenital anemia, hemolytic disease of newborn, neonatal anemia.
erythroblastosis e·ryth·ro·blas·to·sis (ĭ-rĭth'rō-blā-stō'sĭs)
n. pl. e·ryth·ro·blas·to·ses (-sēz)
The abnormal presence of erythroblasts in the blood.