Fax +41 61 306 12 34 E-Mail karger@karger.ch www.karger.com Original Article Gynecol Obstet Invest 2006;61:61–64 DOI: 10.1159/000088603 Effect of Pulsed Estrogen Therapy on Hemostatic Markers in Comparison with Oral Estrogen Regimen in Postmenopausal Women Lourdes Basurto Renata Saucedo Arturo Zárate Carlos Martínez Elizabeth Gaminio Elba Reyes Marcelino Hernandez Endocrine Research Unit, Nacional Medical Center, Instituto Mexicano del Seguro Social, and Department of Hematology, Hospital General de México, Instituto Politécnico Nacional, México City, Mexico 140.6 8 108.7 mU/ml, p ! 0.05). Fibrinogen, ATIII, PC, PS, and PLG were unchanged. Conclusions: Nasal 17 -estra- diol had no effect on the coagulation markers, except a moderate increment in PAI-1. In contrast, oral estrogens elicited a decrement in both VIIa-rTF and PAI-1; however, those changes did not surpass normal limits. Copyright © 2005 S. Karger AG, Basel Introduction It is generally accepted that postmenopausal women exhibit a higher risk of ischemic heart disease than pre- menopausal women, which may be interpreted as evi- dence that deficiency of estrogen contribute to increase the risk of cardiovascular disease [1]. On the basis of these observations with estrogen therapy was proposed in order to obtain a cardioprotective effect [2]. Recent informa- tion regarding the use of hormone replacement therapy (HRT) has been associated with an increased risk of ve- nous thrombosis and a moderately higher relative risk of cardiovascular events [3, 4]; however, there is a large dis- crepancy related to these findings [5, 6]. In addition there are several studies suggesting that these risks are depen- dent on the route of administration of HRT and the in- fluence of progestins [7, 8] . Therefore the adverse effects on coagulation and fibrinolysis have been controversial Key Words Menopause  Hormone replacement therapy  Thrombotic risk factors  Coagulation  Fibrinolysis  Pulsed intranasal estradiol Abstract Background/Aims: Hormone replacement therapy (HRT) is associated with an increased risk of thromboembolism dependent on the type of HRT; therefore, we compared therapy effects of intranasal with oral estrogens on co- agulation and fibrinolysis markers in postmenopausal women. Methods: A randomized study in which 29 healthy hysterectomized women received intranasal 17 - estradiol or oral estrogens for 3 months. Results: There were no significant differences in the baseline character- istics between groups. Those women receiving intrana- sal estradiol showed a mild increment in plasminogen activator inhibitor-1 (PAI-I) (from 6.8 8 3.5 to 9.6 8 3.9 U/ml, p ! 0.01); however, fibrinogen, factor VII-tissue factor complex (VIIa-rTF), antithrombin III (ATIII), protein C (PC) activity, protein S (PS) activity, plasminogen (PLG), and tissue-type plasminogen activator antigen (t-PA) were unchanged. In contrast, oral unopposed estrogens elevated t-PA (from 4.9 8 2.9 to 9.6 8 5.1 ng/ml, p ! 0.01) in parallel with a decrement in PAI-I (from 5.2 8 4.0 to 2.7 8 1.7 U/ml, p ! 0.05) and VIIa-rTF (from 201.2 8 181.0 to Received: June 13, 2005 Accepted after revision: August 10, 2005 Published online: September 28, 2005 Dr. A. Zárate Agrarismo 208-601 México DF–11800 (México) Tel./Fax +52 55 55887521 E-Mail zaratre@att.net.mx © 2005 S. Karger AG, Basel 0378–7346/05/0612–0061$22.00/0 Accessible online at: www.karger.com/goi