Hemophilia

Hemophilia is a medical condition that limits the blood’s ability to clot. It’s almost always inherited and more commonly affects males.

Normally, bleeding stops when blood clots form. This response depends on the combined action of proteins called clotting factors and platelets, a type of blood cell.

In people with hemophilia, the body doesn’t produce enough of a particular clotting factor or makes ineffective factor. The severity of hemophilia symptoms depends on how much clotting factor your body produces. Some people with hemophilia have enough clotting factor to keep symptoms mild. They only need to take occasional precautions. People with lower clotting factor levels experience more severe disease.

Thanks to advances in hemophilia therapies, people with the condition can live full lives — even with severe disease. Researchers are also working on potential cures for hemophilia.

People with hemophilia have increased bleeding. The frequency and circumstances of bleeding depend on how severe hemophilia is:

• Mild hemophilia: People with mild hemophilia may only experience prolonged bleeding with medical or dental procedures or serious injuries. Heavier bleeding may also be experienced during menstruation or delivery. Doctors help people plan for these events when possible and take preventive steps. Learn more about our evaluations of heavy periods.
• Severe hemophilia: People with severe hemophilia bleed more easily from injuries. They may also bleed for no apparent reason, a situation called spontaneous bleeding. Bleeding inside the body can damage muscles and joints, especially the ankles, knees, and elbows. The joints may develop a severe form of arthritis called hemophilic arthropathy. Internal bleeding can also harm organs, including the brain. Fortunately, people can now take effective, ongoing treatment to prevent these complications.

Some families already know they have a history of hemophilia, so children get diagnosed right away. Otherwise, severe hemophilia typically gets noticed in early childhood when it causes symptoms.

With mild hemophilia, age at diagnosis varies. An older girl may get diagnosed after menstruation begins, for example. Others are diagnosed after injuries that cause bleeding or when blood tests done for unrelated reasons show clotting factor changes. Sometimes mild hemophilia is not discovered until adulthood.

Tests for hemophilia look at the blood’s ability to clot and how long the process takes, as well as the amount of particular clotting factors. Genetic testing can look for the inherited change responsible.

With mild or moderate inherited hemophilia, you may only need treatment in special situations, such as before surgery or labor. More severe inherited hemophilia often requires ongoing treatment.

Medications called factor replacements provide the missing clotting factor and promote clotting. Non-factor replacements work to prevent or stop bleeding.

Researchers are also working on ways to restore the genetic information needed to produce the missing clotting factor. The Food and Drug Administration has approved a gene therapy for hemophilia B, with additional clinical trials underway for both hemophilia A and B. Gene therapy can potentially remove the need for frequent treatment.

For acquired hemophilia, doctors typically prescribe therapy that suppresses, or holds back, the immune system.