Plasmatic haemostasis in gonadotrophin-releasing hormone analogue therapy: effects of leuprorelin acetate depot on coagulatory and fibrinolytic activities

The plasmatic parameters of coagulatory and fibrinolytic activity were studied in 15 patients with biopsy-proven endometriosis treated with leuprorelin acetate for 6 months. Bleeding time remained constant, indicating the absence of increased bleeding tendencies. The activity of the main inhibitor of the fibrinolytic response, plasminogen activator inhibitor, was reduced by 25%, suggesting an improvement in fibrinolytic reactivity. Plasma levels of fibrin degradation fragments were reduced by 35%, suggesting a marked reduction in the rate of fibrin generation and degradation. A simultaneous reduction in thrombin-antithrombin III complexes and prothrombin fragment 1 + 2 (-10%) indicated that this effect was induced by reduced procoagulant activity, ie, thrombin generation. These data indicate that in gonadotrophin-releasing hormone (Gn-RH) analogue therapy the basal rate of coagulatory processes is reduced. The frequency and extent of fibrin-generating and degrading processes are reduced, suggesting a beneficial effect of Gn-RH analogues on the risk of thromboembolic disease.