hypoprothrombinemia /hī′pōprōthrom′binē″mē·ə/ [Gk, hypo + L, pro, before; Gk, thrombos, lump, haima, blood] , abnormally reduced plasma prothrombin, characterized by bleeding, poor clot formation, and prolonged prothrombin and partial thromboplastin times. It is usually caused by inadequate synthesis of prothrombin in the liver, vitamin K deficiency, or most often by anticoagulant therapy. Also spelled hypoprothrombinaemia. See also blood clotting.
