Rh Factor
An individual either has, or does not have, the "Rhesus factor" on the surface of their red blood cells. This term strictly refers only to the most immunogenic D antigen of the Rh blood group system, or the Rh- blood group system. The status is usually indicated by Rh positive (Rh+ does have the D antigen) or Rh negative (Rh- does not have the D antigen) suffix to the ABO blood type. However, other antigens of this blood group system are also clinically relevant. These antigens are listed separately (see below: Rh nomenclature). In contrast to the ABO blood group, immunization against Rh can generally only occur through blood transfusion or placental exposure during pregnancy in women.
Read more about this topic: Rh Blood Group System
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