Blood group

Keywords: Blood group typing, BG, ABO subgroup


10 mL blood in plain tube; for some methods, blood in EDTA is preferred - consult pathologist.

Careful labelling of tube, with correct patient details (name, date of birth, identification number) and collection date is essential.


ABO and Rh(D) typing performed routinely.

Patient's red cells tested with anti-A and anti-B sera for ABO (forward) group; with anti-D antiserum for Rh(D) group.

Patient's serum tested with A1 and B cells to check ABO (reverse) group.

Tests are based on the detection of red cell agglutination.

See also Blood group and antibody screen.


Blood grouping is performed prior to possible transfusion, organ transplantation, in pregnancy and investigating certain neonatal conditions. Blood group may aid in interpretation of von Willenbrand studies.

Extended phenotyping (typing for other red cell antigens) may be necessary for patients requiring transfusion when alloantibodies have been detected, for assessment of risk of haemolytic disease of the newborn, and in newly presenting patients with haematological disease where ongoing transfusion support will be required.


Pattern of agglutination determines ABO and Rh(D) blood groups.


Guidelines for Pre-transfusion Testing. 4th ed. Sydney: Australasian Society of Blood Transfusion, 2002. Available at

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