Hemolytic Disease of the Newborn Infant Caused by Maternal Sensitization to the Blood Factor hr’ (c) Report of Two Cases with Special Reference to the Etiologic Significance of Multiple Blood Transfusions in Rh Positive Women Prior to Gestation

H EMOLYTIC DISEASE of the uiewhorn infant due to maternal sensitization to the Hr i)lood factor is no longer au unusual event. Case repou’ts 013 this subject, however, are infrequeuit and iui some iuistances lack sufficient information to elucidate the role of this factor in the pathogenesis of this (lisease. Though some evidence on the occurrence of hemolytic transfusion reactions due to Hr sensitization had beeui preseiited by some investigators” pl’ior to the report of case 2 in a previous communication3 by the present author, ito well described case of an Rh-positive woman sensitized by multiple 1)100(1 transfusiouts prior to pregnancy had as yet heeti reported.