Transdermal estradiol does not impair hemostatic biomarkers in postmenopausal women

Objective: To evaluate the effect of transdermal estradiol therapy (ET) on coagulation and fibrinolysis markers in postmenopausal women. Methods: Prospective open trial study in 59 healthy hysterectomized postmenopausal women. Thirty women received transdermal ET (50 μg per day) during 3 months and 29 women formed the untreated arm. Results: Baseline factor VII-tissue factor complex (VIIa-rTF), fibrinogen and plasminogen activator inhibitor-1 (PAI-1) levels decreased significantly (P<0.01) after therapy. In contrast, tissue-type plasminogen activator antigen (t-PA) levels increased significantly (P<0.01). After ET, there was no difference in protein C activity (PC), protein S activity (PS), plasminogen (PLG), and antithrombin III (ATIII) levels. None of participants reported thromboembolic events. Conclusion: ET elicited a decrement in blood biomarkers implicated in coagulation activation which in turn seemed to improve fibrinolytic activity. These results suggest that transdermal route does not impair thrombotic risk.