How is Hemophilia inherited?

When the father has Hemophilia but the mother does not, none of the sons will have Hemophilia. All of the daughters will carry the Hemophilia gene.


Women who have the Hemophilia gene are called carriers. They sometimes show signs of Hemophilia, and they can pass it on to their children. For each child, there is a 50% chance that a son will have Hemophilia and a 50% chance that a daughter will carry the gene. 

Women can only have Hemophilia if their father has Hemophilia and their mother is a carrier. This is very uncommon.