“Hemophilia is a rare disorder in which your blood doesn’t clot normally because it lacks sufficient blood-clotting proteins (clotting factors). If you have hemophilia, you may bleed for a longer time after an injury than you would if your blood clotted normally.

Small cuts usually aren’t much of a problem. If you have a severe deficiency of the clotting factor protein, the greater health concern is deep bleeding inside your body, especially in your knees, ankles and elbows. That internal bleeding can damage your organs and tissues, and may be life-threatening.”.

MAYO CLINIC