Final answer:
The most common bleeding disorder is von Willebrand disease. Hemophilia A, accounting for the majority of hemophilia cases, is due to a deficiency of factor VIII. Hemophilia B results from a deficiency of factor IX, and both are typically inherited in an X-linked manner.
Step-by-step explanation:
The most common bleeding disorder is von Willebrand disease, which is more prevalent than hemophilia A, B (also known as Christmas disease), or C. Hemophilia A is the most common form of hemophilia, accounting for about 80 percent of hemophilia cases, which is characterized by the inability to synthesize sufficient quantities of factor VIII. Hemophilia B accounts for approximately 20 percent of cases and is due to a deficiency of factor IX. Both A and B are X-linked disorders, usually passed from a carrier mother to her male child. However, von Willebrand disease, which is caused by a defect or deficiency in the von Willebrand factor, is not sex-linked and affects males and females equally.
Patients with hemophilia, including those with hemophilia A and B, typically experience uncontrolled bleeding from even minor injuries and may require regular infusions of clotting factors to prevent bleeding. von Willebrand disease, while also leading to bleeding issues, can sometimes be less severe than hemophilia and can be treated with medications that increase the level of von Willebrand factor in the blood.