Hemophilia is a hereditary condition passed on from parent to child. The blood of a person with hemophilia does not clot normally. People with hemophilia are missing some of the blood proteins called factors that are involved in coagulation or clotting of blood. When the clotting factor is missing, the body cannot stop bleeding by forming a good clot at the site of the injury. This means that bleeding can go on much longer than it should after an injury. Hemophilia A is also called classical hemophilia or Factor VIII (eight) deficiency hemophilia.16 It is called classical hemophilia because it is one of the most common of the factor deficiencies. It is also called Factor VIII deficiency hemophilia because Factor VIII is the missing blood protein that causes the clotting problem.
Hemophilia B is also Factor IX (nine) deficiency hemophilia.16 It is sometimes called Christmas disease after Steven Christmas, the first person to be diagnosed with this form of hemophilia. Hemophilia B is called Factor IX deficiency because Factor IX is the missing blood protein that prevents the normal clotting of blood.
