Hemophilia
Topic Overview
What is hemophilia?
Hemophilia is a rare genetic bleeding disorder. It runs in families and is almost always seen in males. Hemophilia occurs when blood clotting factors don't work as they should. Blood clotting factors help stop bleeding after a cut or injury.
There are two main types of hemophilia:
- Hemophilia A is caused by a lack of active clotting factor VIII (8). About 1 out of every 5,000 male babies is born with hemophilia A.1
- Hemophilia B (Christmas disease) is caused by a lack of active clotting factor IX (9). It is less common and affects 1 out of 30,000 male babies.1
How severe the disease is depends on how much clotting factor is produced and when bleeding most often occurs. There are three levels of hemophilia:
- Mild hemophilia: Clotting factor level is at least 5% of normal. This type might not be noticed unless there is a lot of bleeding after a major injury or surgery.
- Moderate hemophilia: Clotting factor level is 1% to 5% of normal. Bleeding normally follows a fall, sprain, or strain.
- Severe hemophilia: Clotting factor level is less than 1% of normal. Bleeding often happens one or more times a week for no reason.
In rare cases, a person may get acquired hemophilia, a type that does not run in the family. If you have acquired hemophilia, your clotting factors don't work right because your body makes antibodies that attack them.
What causes hemophilia?
Hemophilia A and B are caused by a flaw in a pair of chromosomes. This flaw affects how much clotting factor a person has and how well it works.
What are the symptoms?
Most of the time, hemophilia symptoms are noticed during infancy or childhood. But some people with milder types of the disease may not have symptoms until later in life.
Symptoms noticed in infants include:
- Bleeding into the muscle, which causes a deep bruise after the baby gets a routine vitamin K shot.
- Bleeding that goes on for a long time after a baby is circumcised.
- Bleeding that goes on for a long time after the umbilical cord is cut. This is rare.
Other symptoms include:
- Bleeding into a joint or muscle, which causes pain and swelling.
- Bleeding that is not normal after an injury or surgery.
- Easy bruising.
- Frequent nosebleeds.
- Blood in the urine.
- Bleeding after dental work.
How is hemophilia diagnosed?
Your doctor will do a blood test to find if you have hemophilia. Genetic tests can tell if you are a carrier of the disease. (Only females can be carriers.)
How is it treated?
Most people with this disease can live a normal life with treatment. Hemophilia can be managed with clotting factor replacement therapy. Clotting factors may be injected:
- On a regular schedule, to prevent bleeds.
- As needed. You can give yourself a shot of clotting factor just before you do activities with a high risk for injury or when you think that bleeding has already started.
WebMD Medical Reference from Healthwise
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