Rhesus blod type (Rh. Exposure to cell surface antigens on blood cells can trigger the production of antibodies. The primary antigens that need to be matched to prevent destruction of foreign cells by transfusion reactions are the a & b antigens. In addition, antigen d should also be matched. ( the "d" antigen is one of the 50 rhesus antigens found in humans. If you lack this antigen on your cells you are rh negative.
Rh Blood Group. Rh (rhesus) is a blood group system that is important in pregnancy if there is an incompatibility between mother (rh negative) and baby (rh positive). Does not affect firstborn, but can have serious effects in future births.