Immunohaematology is the science that studies the structure of surface antigens, specific antibodies to antigens, and antigens circulating in blood serum. The detection or, conversely, the absence of certain antigens makes it possible to determine blood group (in particular, according to the ABO system) and the Rh factor, as well as to detect various diseases.
Immunohematological tests are carried out during preconception planning and antenatal care, if there is a suspicion of immune haemolytic disease, in the pre-operative period, and prior to a blood transfusion.