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Updated: Oct 3, 2026

An In Vivo Estrogen Deficiency Mouse Model for Screening Exogenous Estrogen Treatments of Cardiovascular Dysfunction After Menopause
Published on: August 13, 2019
[Effect of hormone replacement therapy on coagulation function in postmenopausal women]
1Department of Obstetrics and Gynecology, Affiliated Hospital, Medical College of Qingdao University, Qingdao 266003, China.
Objective:
To study the effect of hormone replacement therapy (HRT) on coagulation function in postmenopausal women.
Methods:
Fifty-two postmenopausal women were divided into three groups; placebo group (10 cases), estrogen group (19 cases) and estrogen plus progesterone group (23 cases). Twenty healthy premenopausal women served as control group. The coagulation parameters were determined before and 3, 6 months after initiation of HRT.
Results:
The levels of fibrinogen and protein S in postmenopausal women were significantly higher than those in the control group. There was no difference in coagulation parameters before and after placebo administration. After 3-month HRT, the fibrinogen levels in estrogen group and estrogen plus progesterone group significantly decreased and further decreased after 6-month HRT, as compared with before HRT. A significant decrease was also noted in protein S in both groups after 3 month HRT, but returned closely to baseline after 6-month HRT. There was no significant difference in coagulation parameters between estrogen group and estrogen plus progesterone group either before or after HRT.
Conclusion:
HRT significantly decrease the levels of fibrinogen in postmenopausal women.
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