Frequently asked questions

What is the difference between hemophilia A and hemophilia B?

The most common type of hemophilia is called hemophilia A. This means the person does not have enough clotting factor VIII (factor eight).

A less common type is hemophilia B. This person does not have enough clotting factor IX (factor nine).

The result is the same for people with hemophilia A and B: they both bleed for a longer time than normal.

Is hemophilia lifelong?

A person born with hemophilia will have it for life. The level of factor VIII or factor IX in the blood usually stays the same throughout the person’s life.

How common is hemophilia?

Hemophilia is quite rare. About 1 in 10,000 people is born with hemophilia A. About 1 in 50,000 people is born with hemophilia B.

Are there other types of bleeding disorders?

Yes, there are several other factor deficiencies that also cause abnormal bleeding. These include deficiencies in factors I, II, V, VII, X, XI, XIII and von Willebrand factor. The most severe forms of these deficiencies are even rarer than hemophilia A and B.

More information on von Willebrand disease, rare clotting factor deficiencies, and inherited platelet disorders.

How serious is hemophilia?

The severity of hemophilia depends on the amount of factor VIII or factor IX in the blood.

There are three levels of severity: mild, moderate, and severe. People with severe hemophilia usually bleed frequently into their muscles or joints. They may bleed one to two times per week. Bleeding is often spontaneous, which means it happens for no obvious reason.

People with moderate hemophilia bleed less often, usually after an injury. Cases of hemophilia vary, however, and a person with moderate hemophilia can bleed spontaneously.

People with mild hemophilia usually bleed only as a result of surgery or major injury.

What is acquired hemophilia?

In rare cases, a person can develop hemophilia later in life. The majority of cases involve middle-aged or elderly people, or young women who have recently given birth or are in the later stages of pregnancy.

Acquired hemophilia is usually caused by the development of antibodies to factor VIII or factor IX: the body’s immune system destroys its own naturally produced factor VIII.

This condition often resolves with appropriate treatment.

Does hemophilia only affect men?

For many years, people believed that only men could have symptoms of hemophilia and that women who "carry" the hemophilia gene do not experience symptoms themselves. We now know that many carriers do experience symptoms of hemophilia. As our knowledge about the disorder has increased, so has our understanding of why and how women can be affected. A woman who has less than 40 per cent of the normal level of clotting factor is no different from a man with the same factor levels—she has hemophilia. Some carriers have symptoms of hemophilia even though their clotting factor levels are above 40 per cent. A woman with levels of 40-60 per cent of the normal amount of clotting factor who experiences abnormal bleeding is called a symptomatic carrier.

Click here for more information on carriers and women with hemophilia.

Are there any precautions a carrier of hemophilia should take if she becomes pregnant?

A carrier’s hematologist should be involved in the supervision of the pregnancy and should consult with the obstetrician before delivery. It is not necessary to perform prenatal diagnosis just for management of the pregnancy. This is only done if termination of pregnancy is being considered in the case of an affected child.
The factor VIII level (but not factor IX) tends to rise during pregnancy but should be checked sometime in the month or so before delivery.

A normal vaginal delivery is perfectly acceptable even if the fetus is male and at risk of hemophilia. Epidural anesthesia does not usually present a problem and is generally possible if the patient’s factor level is 40 percent or more. A cord blood sample after delivery will be used to check if a male baby has hemophilia. 

How is hemophilia diagnosed?

Hemophilia is diagnosed by taking a blood sample and measuring the level of factor activity in the blood. Hemophilia A is diagnosed by testing the level of factor VIII coagulation activity in the blood. Hemophilia B is diagnosed by measuring the level of factor IX activity.

If the mother is a carrier, testing can be done before a baby is born. Prenatal diagnosis can be done at 9 to 11 weeks by chorionic villus sampling (CVS) or by fetal blood sampling at a later stage (18 or more weeks).

These tests can be done at a hemophilia treatment centre. Consult the Global Treatment Centre Directory for information on treatment centres around the world. 

Where do bleeds occur?

Most bleeding in hemophilia occurs internally, into the joints or muscles.

The joints that are most often affected are the knee, ankle, and elbow. Repeated bleeding without prompt treatment can damage the cartilage and the bone in a joint, leading to chronic arthritis and disability.

The most serious muscle bleeds are the iliopsoas muscle (the front of the groin area), the forearm, and the calf.

Some bleeds can be life-threatening and require immediate treatment. These include bleeds in the head, throat, gut, or iliopsoas.

Are bruises dangerous?

Bruises are very common in children with hemophilia. A bruise is not usually cause for alarm, unless it is on the person’s head or neck, the person has a hard time moving, the bruise hurts, the lump in the bruise gets larger or does not go away, or if there is numbness or a tingling feeling along with the bruising. In any of these cases, a physician or local hemophilia treatment centre should be consulted.

Should people with hemophilia avoid aspirin and other similar non-steroidal anti-inflammatory drugs (NSAIDs)?

People with hemophilia should not take aspirin (ASA or acetylsalicyclic acid), or anything containing aspirin, as well as other NSAIDs, because they interfere with the stickiness of platelets and can make bleeding problems worse. Paracetamol (acetominophen) is a perfectly safe alternative to aspirin to relieve pain.

A list of medications that can interfere with bleeding.

Should people with hemophilia exercise and play sports?

Some people with hemophilia avoid exercise because they think it may cause bleeds, but exercise can actually help prevent them. Strong muscles help protect someone who has hemophilia from spontaneous bleeds and joint damage.

Sport is an important activity for young people. It helps build muscle and develop mental concentration and coordination. However, some sports are riskier than others, and the benefits must be weighed against the risks. The severity of a person’s hemophilia should also be considered when choosing a sport. Sports like swimming, badminton, cycling, and walking are safe for most people with hemophilia, while American football, rugby, and boxing are usually not recommended.

What are inhibitors?

Inhibitors are a serious medical problem that can occur when a person with hemophilia has an immune response to treatment with clotting factor concentrates.

Sometimes, a person's immune system reacts to proteins in factor concentrates as if they were harmful foreign substances because the body has never seen them before. When this happens, inhibitors (also called antibodies) form in the blood to fight against the foreign factor proteins. This stops the factor concentrates from being able to fix the bleeding problem.

Bleeding is very hard to control in someone with hemophilia who develops inhibitors.

More information on inhibitors.

What is prophylaxis?

Prophylaxis is the regular use of clotting factor concentrates to prevent bleeds before they start. Injections of clotting factor are given one, two or three times a week to maintain a constant level of factor VIII or IX in the bloodstream.

Prophylaxis can help reduce or prevent joint damage and improve the quality of life of people with hemophilia. In countries with access to adequate quantities of clotting factor concentrates, this is becoming the normal mode of treatment for younger patients, and can be started when the veins are well developed (usually between the ages of two and four years).

What is a venous access device (port-a-cath)?

A port-a-cath, or implantable venous access device (VAD), is a device that’s implanted under the skin, usually in the chest but sometimes in the arm. It has a reservoir connected to a catheter, which is then threaded into a vein. This way, medications and fluids can be injected easily, without having to ‘find a vein’ for each injection.

VADs have made prophylaxis (regular infusions of factor concentrates) in hemophilia much easier for families. However, there are risks. Some studies have shown an infection rate as high as 50%. These infections can usually be treated with intravenous antibiotics but sometimes the device must be removed. There is also a risk of clots forming at the tip of the catheter. Like for any other procedure, each family must weigh the risks and benefits.

Is there a cure for hemophilia?

There is no cure for hemophilia. Gene therapy remains an exciting possibility and holds out the prospect of a partial or complete cure. There are many technical obstacles to overcome, but research currently underway is encouraging.

Technically, a liver transplant can cure hemophilia, since coagulation factors are produced by cells inside the liver. However, the risks of surgery and the requirement for lifelong medication to prevent rejection of the transplanted organ may outweigh the benefits.

What is the life expectancy of someone with hemophilia?

The life expectancy of someone with hemophilia varies depending on whether they receive proper treatment. Without adequate treatment, many people with hemophilia die before they reach adulthood. However, with proper treatment, life expectancy for people with hemophilia is about 10 years less than that of males without hemophilia, and children can look forward to a normal life expectancy.


Updated May 2012


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