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Haemophilia is an inherited condition that affects the blood's ability to clot.

Normally, when you cut yourself, substances in the blood known as clotting factors combine with blood cells called platelets to make the blood sticky. This makes the bleeding stop eventually.

However, in haemophilia, there aren't as many clotting factors as there should bein the blood. This means that someone with the condition bleeds for longer than usual.

The condition is passed to a child by one or both of their parents.

Most cases are mild, but people with severe haemophilia experience symptoms, which require ongoing care.

People with severe haemophiliaoften experience internal bleeding. This usually occurs around the joints and muscles, causing pain and stiffness. It can also lead to joint damage over time.

This isn't an inherited condition, but is caused by the immune system (the body's natural defence against infection and illness) attacking the clotting factors in the blood.

This article is about haemophilia A and B.

Who is affected?

Because of the way the condition is inherited most affected are man.

Worldwide, it's estimated that one boy in every 5,000 will be born with haemophilia A and one boy in every 30,000 will be born with haemophilia B.

However, some females who carry the haemophilia gene may also experience some bleeding problems, such as heavy periods. There's also the chance that a girl could be born with haemophilia if both parents have the haemophilia gene.

If you have a family history of haemophilia, you can have tests before, during and after pregnancy to determine if your child has the condition. If there's no family history, haemophilia tends to be diagnosed when symptoms appear in childhood.

Injections are usually only given in milder casesin response to prolonged bleeding, whereas more severe cases are treated with regular injections to prevent bleeding.


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Content supplied by the NHS Website

Medically Reviewed by a doctor on 4 Jan 2017