• 04-24-2024

Hemophilia is usually an inherited condition in which blood does not clot properly.

Blood circulates throughout the body through veins, arteries, and capillaries. When cut, the skin is injured, as well as the capillaries, from which blood begins to flow. To stop bleeding, the capillary narrows, and special blood cells – platelets – form a plug to patch the hole. Plasma (the liquid part of the blood) contains many clotting factors that help platelets to make a plug and stop bleeding.

In hemophilia, there is no or too little blood clotting factor. Because of this, the clot, which is supposed to stop the blood, does not form properly and the bleeding continues for a longer time than usual.

Plasma contains many clotting factors. Each factor is numbered with a Roman numeral. The two most common factors affecting blood clotting are factor VIII (8) and factor IX (9).

Types of hemophilia

There are several types of hemophilia, but two of them are the most common:

Hemophilia A. The blood lacks clotting factor VIII. Approximately 85% of all hemophiliacs.

Hemophilia B. The blood lacks clotting factor IX.

Hemophilia is also classified according to its severity. It can be mild, moderate, or severe, depending on the level of the clotting factor.

Symptoms of hemophilia

Symptoms of hemophilia vary depending on the severity of the disorder. In most cases, symptoms appear during childhood. But sometimes, with a mild hemophilia, the disease can be detected in adulthood.

The most common symptoms of hemophilia are:

  • Blood in urine or stool.
  • Frequent nosebleeds that are difficult to stop.
  • Many large or deep bruises.
  • Bleeding into the joints or muscles causing pain and swelling.
  • Bleeding from the gums.
  • Bleeding after injections, vaccinations.
  • Too much bleeding after injuries, cuts, and during surgery.

Causes of hemophilia

In most cases, hemophilia is hereditary. However, in rare cases, hemophilia may not be congenital, but acquired. Acquired hemophilia is an autoimmune disease in which the immune system attacks the clotting factors, and they cannot function properly.

Acquired hemophilia can be caused by pregnancy, cancer, autoimmune conditions, multiple sclerosis, as a reaction to certain medications.


Hemophilia is much more common in men than in women.

Hemophilia is caused by a defect in the genes responsible for blood clotting factors. In the most common types of hemophilia, the defective genes are found on the X chromosome.

The X chromosome is one of the sex chromosomes responsible for the biological sex of a child. Each person has two sex chromosomes, one from each parent. Girls inherit the X chromosome from their mother and the X chromosome from their father – XX. Boys inherit the X chromosome from their mother and the Y chromosome from their father – XY.

If a boy receives an X chromosome with a defective gene from his mother, he will have hemophilia. Girls with one affected X chromosome in most will be a “carrier” of hemophilia because they have a second healthy X chromosome. A carrier means that the girl will not have symptoms of hemophilia, but she can pass the disease on to her children.

It is very rare for females to have hemophilia. Hemophilia occurs when a woman has both X chromosomes with defective genes.

Sometimes, however, a woman with one affected X chromosome will develop symptoms of hemophilia if the clotting factors are moderately decreased.


Treatment for hemophilia typically involves replacing the missing clotting factor in the blood. This can be done through injections of clotting factor concentrates. The frequency of these injections depends on the severity of the hemophilia and the individual's bleeding patterns. Some individuals may require regular prophylactic injections to prevent bleeding episodes, while others may only need treatment when bleeding occurs.

In addition to medical treatment, individuals with hemophilia may also benefit from physical therapy to strengthen muscles and joints, which can help prevent bleeding into these areas. Furthermore, it's essential for individuals with hemophilia and their caregivers to receive education and support to learn how to manage the condition effectively, including recognizing signs of bleeding, administering clotting factor replacement therapy, and taking precautions to prevent injuries.

Gene Therapy

In recent years, there have been significant advancements in the treatment of hemophilia, particularly with the development of longer-acting clotting factor concentrates and gene therapy. Gene therapy, in particular, holds great promise for individuals with hemophilia, as it aims to address the underlying genetic cause of the condition by introducing a functional copy of the defective gene into the body. Clinical trials of gene therapy for hemophilia have shown promising results, with some patients achieving sustained production of the missing clotting factor and significantly reduced bleeding episodes.

Prenatal Testing

While hemophilia is primarily inherited, prenatal testing and genetic counseling are available for families with a history of the condition. Prenatal testing can determine whether a fetus is affected by hemophilia, allowing parents to make informed decisions about their pregnancy and plan for appropriate medical care after birth. Genetic counseling provides families with information about the inheritance pattern of hemophilia and the likelihood of passing the condition on to future generations.

Despite significant progress in the understanding and treatment of hemophilia, challenges remain, particularly in regions with limited access to healthcare resources. Improving access to diagnosis, treatment, and supportive care services is crucial to ensuring that individuals with hemophilia can lead healthy and fulfilling lives. Additionally, ongoing research efforts continue to explore new treatment modalities and approaches to improve outcomes and quality of life for individuals with hemophilia and their families.

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