Hemophilia occurs due to a deficiency in certain blood clotting factors, specifically factor VIII in Hemophilia A and factor IX in Hemophilia B. These are X-linked disorders, meaning they primarily affect males, although females can be carriers and occasionally show symptoms. The severity of hemophilia is classified based on factor activity levels, with severe cases showing less than 1% of normal clotting factor activity.

People with hemophilia often experience excessive bleeding from minor injuries or spontaneous bleeding episodes. Common sites of bleeding include joints, muscles, and mucous membranes like the gums and nose. Joint bleeding, known as hemarthrosis, is particularly common and can lead to joint damage over time.

Diagnosing hemophilia involves assessing personal and family medical histories, along with specific blood tests. These tests measure the levels of clotting factors in the blood and help differentiate hemophilia from other bleeding disorders. Genetic testing can confirm carrier status in females and is crucial for family planning.

Understanding the symptoms and diagnosis of hemophilia is crucial for effective management and treatment.