Hemophilia is a rare disorder in which your blood doesn't clot normally because it lacks sufficient blood-clotting proteins which are clotting factors. It makes you bleed for a longer time after an injury because your blood does not clot normally. Hemophilia is an inherited (genetic) disorder.
Deep bleeding inside your body, especially in your knees, ankles and elbows can damage your organs and tissues which may be life-threatening.
Hemophilia occurs when you have a deficiency in one of clotting factors which form a clot to stop the bleeding.
Most forms of hemophilia are inferited. However, some people get hemophilia due to an unexpected change (spontaneous mutation) occurs in one of the genes associated with hemophilia. Acquired hemophilia is a rare variety of the condition that occurs when the immune system of a person with pregnancy, autoimmune conditions, cancer, or multiple sclerosis attacks clotting factors in the blood.
Hemophilia almost always occurs in boys and is passed from mother to son through one of the mother's genes. Therefore most women with the defective gene are simply carriers and experience no signs or symptoms of hemophilia.