Hello,

The accurate grouping of blood is very important when it comes to having a blood transfusion. If blood is given to a patient that has a blood type that is incompatible with the blood type of the blood that the patient receives, it can be fatal because of intravenous clumping in the patient's blood. Both the ABO and the Rh blood types are important when it comes to matching blood types for transfusion. Platelets help the blood to clot. The Rh group has 50 defined blood-group antigens, but the most important from a classification and blood compatibility point of view is the RhD antigen.