Haemophilia

What is haemophilia?

Haemophilia is a severe inherited bleeding disorder in which the blood does not clot properly.

Depending on the residual activity of the partially or completely missing clotting factor, this leads to spontaneous bleeding, mostly into the joints. People with haemophilia do not bleed more than people without haemophilia, but they bleed longer.1 Furthermore, the recurrent bleeding can lead to considerable damage, especially in the joints.

Haemophilia is always passed on from the mother to the male offspring, as it is an X-linked recessive trait. In the very rare case that a girl has haemophilia, the father with haemophilia is also involved in the transmission in addition to the mother.

As the most common form of haemophilia, haemophilia A affects 1,000,000 people worldwide1 and about 600 people in Switzerland.2