How Is Hemophilia Diagnosed?

If hemophilia is suspected, or if you appear to have a bleeding problem, your doctor will take your personal and family medical histories. This will reveal whether you or anyone in your family has a history of frequent and/or heavy bleeding and bruising.

You also will likely have a physical exam and blood tests to diagnose hemophilia. Blood tests are used to find out:

• How long it takes for your blood to clot
• Whether your blood has low levels of any of the clotting factors
• Whether one of the clotting factors is completely missing from your blood

The test results will show whether you have hemophilia, what type of hemophilia you have, and how severe it is.

Hemophilia A and B are classified as mild, moderate, or severe, depending on the amount of clotting factor VIII or IX in the blood.

The severity of symptoms can overlap between the categories. For example, some people who have mild hemophilia may have bleeding problems almost as often or as problematic as some people who have moderate hemophilia.

Severe hemophilia can cause serious bleeding problems in babies. Therefore, children who have severe hemophilia usually are diagnosed during the first year of life. People who have milder forms of hemophilia may not be diagnosed until they're adults.

The bleeding problems of hemophilia A and hemophilia B are the same. Only special blood tests can tell which type of the disorder a person has. Knowing which type is important because the treatments are different.

Pregnant women who are known hemophilia carriers can have the disorder diagnosed in their unborn children as early as 10 weeks into their pregnancies.

Women who are hemophilia carriers also can have "preimplantation diagnosis" to have children who don't have hemophilia. For this process, women have their eggs removed and then fertilized by sperm in a laboratory. The embryos that result from this fertilization are then tested for hemophilia. Only embryos that lack the condition will be implanted in the womb.