RH Groups

In 1939, a mother gave birth to a stillborn baby and underwent blood transfusion with ABO-matched blood from her husband. This resulted in a hemolytic transfusion reaction (HTR). Levine and Stetson postulated that a novel antigen was present in the baby and father, which was absent in the mother. Therefore, the mother’s immune system recognized this antigen and produced antibodies against it. This condition has been known as the hemolytic disease of the newborn for a long period of time. Since the antenatal management of the fetus has been developed, the term has been modified to hemolytic disease of the fetus and newborn (HDFN). This case led to the discovery of the antibody against the first antigen of the RH blood group system, the D antigen. To date, 56 antigens have been recognized within the RH blood group system. The five main antigens are D, C, c, E, and e. As observed in the above-mentioned case, the antibodies against these antigens are implicated in HTR and HDFN.