Comparison of the effects of tibolone and estrogen therapy on hemostasis in surgical menopause: a randomized, double-blind, placebo-controlled study.
OBJECTIVE
To examine the effects of unopposed estrogen (E) and tibolone therapy on coagulation and natural anticoagulant systems in surgical menopause.


METHODS
A randomized, double-blind, placebo-controlled study.


METHODS
University hospital clinic in Turkey.


METHODS
Ninety healthy surgically postmenopausal women.


METHODS
Ninety surgically postmenopausal women were randomized into three groups: unopposed conjugated ET (0.625 mg/d, group 1), tibolone (2.5 mg/d, group 2), and identical tablets of placebo (group 3).


METHODS
Effects on parameters in the clotting cascade at baseline and after 24 weeks of treatment.


RESULTS
After 6 months, fibrinogen, lipoprotein (a), and factor VIIa were decreased, and activated partial thromboplastin time was increased significantly in the ET group compared with in the placebo group. However, tibolone significantly decreased only the serum levels of factor VIIa and factor IX and prolonged the activated partial thromboplastin time, compared with placebo group. In addition, conjugated ET caused a significantly greater decrease in serum fibrinogen level than did tibolone.


CONCLUSIONS
Neither E nor tibolone therapy led to activation of coagulation in the surgically menopausal women. Both preparations changed the overall hemostatic balance to a more fibrinolytic state.
Demirol
Aygul
A
Clinic for Womens' Health, Infertility, and IVF Center, Ankara, Turkey.
Guven
Suleyman
S
Guvendag Guven
Emine Seda
ES
Kirazli
Serafettin
S
Gurgan
Timur
T
Ayhan
Ali
A
D000990:Antithrombin III / Q000032:analysis; D001779:Blood Coagulation Factors / Q000032:analysis; D004311:Double-Blind Method; D004966:Estrogens, Conjugated (USP) / Q000494:pharmacology*; D005260:Female; D006487:Hemostasis / Q000187:drug effects*; D006801:Humans; D007044:Hysterectomy; D017270:Lipoprotein(a) / Q000097:blood; D008593:Menopause; D008875:Middle Aged; D009652:Norpregnenes / Q000494:pharmacology*; D010314:Partial Thromboplastin Time; D011446:Prospective Studies; D012489:Salpingostomy; D020246:Venous Thrombosis / Q000209:etiology
D001779:Blood Coagulation Factors; D004966:Estrogens, Conjugated (USP); D017270:Lipoprotein(a); D009652:Norpregnenes; D000990:Antithrombin III; C027385:tibolone