 Postpartum prophylactic treatment of RhD negative women with anti-D immunoglobulin to prevent RhD Disease, or hemolytic disease of the fetusnewborn, was initiated in the 1960s. In the mid 1980s, the routine administration of antenatal anti-D immunoglobulin became the standard of care as well. Although these treatments have dramatically reduced the incidence of RhD Disease, approximately 40 of all RhD negative pregnancies continue to receive unnecessary injections of antenatal anti-D immunoglobulin. 