Haemophilia is a inherited disorder that affects males and very occasionally symptoms can occur in females. This disorder results in prolonged bleeding from injury or following surgery. In severe cases spontaneous bleeds can occur in large joints and muscles. Occasionally bleeds can occur in vital organs for example the brain. Haemophilia is due to a deficiency of a clotting protein Factor VIII (Haemophilia A) of Factor IX (Haemophilia B). The deficiency can be mild, moderate or severe.

Treatment involves an injection of a concentrated form of the missing clotting protein into a vein. From there the clotting protein travels to the site of the injury to enhance the healing process. The clotting protein cannot be taken by mouth as enzymes in the stomach easily destroy it. The clotting protein can be artificially made or extracted from blood donations from the Red Cross Transfusion Service. Recently rather than treat persons affected following a bleed, the concentrated clotting protein is given regularly to prevent bleeds from occurring. This has resulted in far fewer complications for those with Haemophilia.

Von Willebrands disease (VWD) is a more common inherited bleeding disorder but usually less severe than haemophilia. VWD can affect both males and females. VWD is due to an absence of a protein that supports the first phase of the clotting process. Without the Von Willebrand protein, platelets do not attach to the blood vessel and bleeding continues.