Factor I
Also known as fibrinogen deficiency, this rare disorder affects both platelets and clotting and is found in both males and females. The complete absence of Factor I, or afibrinogenemia, is usually discovered in newborns, due to bleeding from the umbilical cord or after circumcision. The incidence of Factor I deficiency is estimated at 1 to 2 per million. Another variation is called dysfibrinogenemia, where there is an abnormal form of fibrinogen, resulting in defective clot formation.2
- Common symptoms include easy bruising, nose and mouth bleeds, and soft tissue bleeds. Joint and muscle bleeds are possible. Women may experience excessive menstrual bleeding2
Factor II
This bleeding disorder, also known as prothrombin deficiency, is extremely rare and affects both males and females equally. The estimated rate of occurrence is 1 in 2,000,000 people worldwide.3
- Common symptoms include excessive menstrual bleeding, easy bruising, and hemorrhage after trauma3
Factor V
Factor V deficiency is also known as parahemophilia. First identified in Norway in 1943, this disorder has been estimated to occur in only about 1 in 1,000,000 people and affects both men and women equally.4
- Common symptoms include nose bleeds, bruising, and excessive menstrual bleeding4
Factor VII
This rare disorder, also known as proconvertin deficiency or Alexander's disease, is often diagnosed at birth. The incidence of Factor VII deficiency is estimated to be 1 in 300,000 to 500,000 people, and affects men and women equally.5
- Common symptoms include sustained bleeding in newborns' central nervous system or gastrointestinal tract and excessive menstrual bleeding in women; children and adults may also experience spontaneous bleeding from the nose, gums, or genitourinary tract5
Factor X
Factor X deficiency can also be known as Stuart-Prower factor deficiency, after the first 2 people identified with this bleeding disorder. This condition has been estimated to occur in 1 in 500,000 to 1,000,000 people and affects men and women equally.6
- Common symptoms may include mild to severe symptoms, including nose bleeds, frequent bruising, excessive menstrual bleeding, and intramuscular bleeding; bleeding within the skull may be severe6
Factor XI
This rare disorder is also known as hemophilia C. It occurs in approximately 1 in 100,000 people, although it is found more frequently among some ethnic groups (primarily those with Jewish ethnicity of eastern European descent). Also, unlike hemophilia A and B, the rates of this disorder are equal among men and women.7
- Symptoms are usually milder than other bleeding disorders, but some patients may experience frequent nose bleeds or soft tissue bleeds while others may have delayed bleeding after procedures like tooth extractions8
Factor XII
Factor XII deficiency can also be known as Hageman factor deficiency, after the first patient diagnosed with the disorder. First identified in 1955, this disorder occurs in an estimated 1 in 1,000,000 people and affects men and women equally.9
- This disorder is unusual in that bleeding symptoms are rare. Patients with this deficiency have poor wound healing but most do not have bleeding issues even after major surgeries9
Factor XIII
In this rare disorder, also known as fibrin stabilizing factor deficiency, the affected person lacks the necessary factor for proper clot formation and wound healing. Without factor XIII, a clot forms normally, but the clot breaks down and bleeding starts again. This disorder is another rare inherited factor deficiency, occurring in an estimated 1 in 5,000,000 people and affects men and women equally10
- Symptoms include bleeding after birth from the umbilical cord. Adults and children can experience bruising, muscle bleeds, and delayed bleeding after surgery. Bleeding into the brain, a life-threatening condition, can occur spontaneously10