This test determines an individual's ABO blood group and Rh(D) status using standardized agglutination methods. The four ABO groups are defined by antigens present on red blood cells, while Rh(D) status indicates the presence or absence of the D antigen.
Knowing both is critical before any blood transfusion, organ transplantation, or surgical procedure where transfusion may be required, as incompatible blood can trigger severe immune reactions. It is also a routine prenatal test: Rh-negative mothers carrying Rh-positive babies may require Rh immune globulin (RhoGAM) injections to prevent hemolytic disease of the newborn. Sample type is whole blood collected in an EDTA tube.