Sensitization of Rh-Negative Daughters by Their Rh-Positive Mothers

THE prediction of immunologic tolerance by Burnett and Fenner1 suggested that tolerance to the Rh antigen might be induced in Rh-negative girls born of Rh-positive mothers.2 Immunologic tolerance was considered possible because maternal red cells cross the placenta to the fetus in at least some pregnancies.3 4 5 6 A contrary opinion held that the few authenticated cases of hemolytic disease, in first-born infants of mothers who had received no known stimulus, might be due to sensitization acquired by the mother in utero.7 , 8 This study was undertaken to determine whether Rh-positive mothers induce immunologic tolerance or primary sensitization in their Rh-negative daughters . . .