1. Ada
  2. Conditions
  3. Hemophilia


Written by Ada’s Medical Knowledge Team

Updated on

What is hemophilia?

Hemophilia is a hereditary genetic bleeding disorder which causes blood clotting problems due to a lack in the proteins needed for normal blood clotting to take place. This causes people with hemophilia to bleed more than other people, for example, after injuries or surgeries. This condition is passed on the X chromosome, and for this reason, affects males more commonly than females. Diagnosis is made based on the symptoms, whether a family member is known to have hemophilia and by testing the clotting function of the blood. Preventing injuries and taking extra clotting proteins are two ways to prevent the complications of this condition. With good management, the outlook for people with hemophilia is good, although it depends on the severity of the clotting factor deficiency.


Hemophilia is an inherited bleeding disorder caused by mutation in a gene. The blood clotting problems occur because people with hemophilia have a lack of the proteins needed for normal blood clotting to take place. There are two types of hemophilia, type A (the more severe and common type) and type B (also known as Christmas disease). In mild hemophilia, a person’s blood has some ability to clot, but in people with the severe type, the blood may have very few or no clotting proteins at all. Because it is a genetic disorder, hemophilia tends to run in families, however, around one third of people diagnosed are the first person in their family to have hemophilia. These people can pass the gene to their children. This gene is on the X chromosome and therefore, because they only have one, males are more likely to have hemophilia than females.


People with hemophilia tend to bruise or bleed excessively after small incidents or procedures. They may have a tendency to bruise, or to have severe episodes of nose bleeding, gum bleeding or even bleeding into joints. Women with hemophilia may have heavy periods. People with hemophilia are also at increased risk of bleeding in the bowel, which may cause red or black bowel movements.


The diagnosis is based on the symptoms of the affected person, whether any other people in the family are known to have hemophilia, physical examination and tests for the ability of the blood to clot. Blood tests may reveal that the blood takes longer than usual to clot, and low levels or an absence of some of the proteins needed for normal blood clotting.


Treatment of hemophilia depends on the ability of the blood to clot. People whose blood has some ability to clot may receive an injection to improve blood clotting before they have a procedure which may cause bleeding, such as dental work. People whose blood has little or no ability to clot alone may need to have regular injection to protect them in case of accidents. Treatment should be carried out by an expert in the field. People with hemophilia should wear a medic alert bracelet or carry a ID card with them in case of emergencies.


Preventing injuries is very important to avoid bleeding. People with hemophilia might need to receive clotting factors before they have a procedure which can cause bleeding. Medications to thin the blood should not be taken.

Other names for hemophilia

  • Christmas disease

Share this article: