Factor X (Stuart-Prower Factor)
Factor X is a coagulation factor essential to the normal clotting process. Production of factor X takes place in the liver and requires vitamin K. Factor X deficiency is inherited as an autosomal recessive trait manifest by prolonged nose bleeds, gastrointestinal hemorrhage, abnormally heavy menstrual bleeding, blood in the urine, and bleeding into joints. Pregnancy in women with factor X deficiency is often associated with recurrent spontaneous abortion, placenta abruptio, and premature birth. Factor X is also called Stuart-Prower factor because Mr. Stuart and Miss Prower were the first persons shown to have deficiency of this factor.