Inherited Thrombophilias
Thrombophilia is a term that can refer to almost any risk factor (such as the postoperative state), which could predispose to thrombosis. Thrombophilia can be inherited or acquired. The normal response to blood vessel injury is formation of a clot. Platelets adhere to damaged endothelium at the site of injury via von Willebrand factor, are activated, aggregate and form an initial platelet plug. The aggregated platelets are enmeshed by fibrin, which has been converted from soluble fibrinogen by the enzyme thrombin, to form a more stable clot. Increased levels of coagulation factors, decreased levels of the natural anticoagulants, decreased levels of fibrinolytic factors, or increased levels of fibrinolytic inhibitors can each increase the risk of thrombosis and such changes can be inherited. Prospective studies have found no associations between thrombophilia and adverse pregnancy outcome or only weak ones.