Haemophilia is a blood disorder. People with haemophilia (PWH) do not bleed any faster than normal, but they can bleed for longer, because their blood does not have enough clotting factor.

Haemophilia is considered a rare disease. The most common type of haemophilia is called haemophilia A. People with haemophilia A do not have enough clotting factor VIII (factor eight). About 21 of every 100,000 males have haemophilia A.

A less common type is called haemophilia B. People with haemophilia B do not have enough clotting factor IX (factor nine). About 4 in 100,000 males have haemophilia B.

The result is the same for people with haemophilia A and B, that is, they bleed for a longer time than normal.

For many years, people believed that only men and boys could have symptoms of haemophilia, and that women who “carry” the haemophilia gene do not experience symptoms themselves. We now know that many women and girls do experience symptoms of haemophilia.

People are born with haemophilia. They cannot catch it from someone. Haemophilia is usually inherited, meaning that it is passed on through a parent’s genes.

haemophilia cannot be cured but treatments can help control symptoms.

For more information about haemophilia, see the World Federation of haemophilia website.

Article published date: 14 April 2026