Hemophilia is an inherited bleeding disorder primarily affecting males—but females can also have hemophilia.
What is hemophilia?
Hemophilia is a bleeding disorder in which the blood does not clot properly.
It is caused by a lack of clotting factor proteins in the blood.
As a result, people with hemophilia may experience excessive and longer-than-usual bleeding after physical injury or trauma; but they can also experience bleeding without injury or any obvious trigger.
People with hemophilia can use treatments called clotting factor concentrates (also known as “factor”) to replace the missing clotting factor proteins in their blood to stop bleeding.
This is typically done by injecting factor into a person’s vein.
Often, the best choice for good, quality medical care for people with hemophilia is from a comprehensive hemophilia treatment center (HTC).
Find an HTC near you.
What causes hemophilia?
Hemophilia is caused by a mutation (change) in one of the genes that provides instructions within cells for making clotting factor proteins in the blood.
This mutation results in hemophilia by preventing the clotting factor protein from working properly or causing it to be missing altogether.
These genes are located on the X chromosome. Males have one X and one Y chromosome (XY) and females have two X chromosomes (XX).
A male inherits his X chromosome from his mother and his Y chromosome from his father. A females inherits one X chromosome from each parent.
A male can have hemophilia if he inherits an affected X chromosome (an X chromosome with a mutation in the gene that causes hemophilia) from his mother.
Hemophilia can affect women, too
Females can also have hemophilia, but it is much rarer. When a female has hemophilia, both X chromosomes are affected or one is affected and the other is missing or non-functioning.
In these females, bleeding symptoms can be similar to males with hemophilia. When a female has one affected X chromosome, she is a “carrier” of hemophilia. Being a female carrier of hemophilia is not the same as having hemophilia; although female carriers may experience symptoms of hemophilia.
A female carrier can also pass the affected X chromosome on to her children.
Sometimes females with bleeding symptoms are not tested for hemophilia; because there is often a misbelief that women can’t have hemophilia but can only be carriers.
Thus, women with hemophilia might not get an accurate diagnosis.
Although it is rarer for women to have hemophilia when compared to men, women can also have the condition.
It is important to raise awareness about this fact to help women with hemophilia receive the care and support they need to live healthy lives.