[Hemostatic balance during treatment with the newest contraceptives]

Thirty-four healthy young women were allocated to 12 consecutive cycles of treatment with monophasic combinations of: 20 micrograms ethinyl estradiol and 150 micrograms desogestrel (n = 15) or 30 micrograms ethinyl estradiol and 75 micrograms gestodene (n = 19). In both groups plasma levels of fibrinogen and factor VII increased while the capacity of coagulation inhibition was affected by increased protein C and decreased protein S levels. Increased fibrinolytic capacity was indicated by elevated activity and reduced antigen levels of tissue plasminogen activator and reduced activity and concentration of tissue plasminogen activator inhibitor. The ratio between thrombin-antithrombin-III-complexes and fibrin degradation products were unchanged signifying no effect of hormonal intake on the balance between thrombin formation and fibrin resolution. In conclusion, the dynamic balance between generation and resolution of fibrin was undisturbed during treatment with both hormonal compounds and our findings do not provide evidence for increased risk of thrombosis in normal women.