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Updated: Apr 12, 2026

An In Vivo Estrogen Deficiency Mouse Model for Screening Exogenous Estrogen Treatments of Cardiovascular Dysfunction After Menopause
Published on: August 13, 2019
Hormone replacement therapy: 1815.84 woman-years of follow-up main clinical events
Background:
One hundred and eighty-five women with a mean age of 50.71 (SD=5.58) years upon initiation of treatment were studied before, and during, treatment.
Materials And Methods:
Included in the profile of patients under study were family and personal histories, gynecological and breast examinations. Population age: a) <60 years old, 171 women (92.43%), and b) aged 60 years or older, 14 women (7.57%). Dosage comprised both 0.625 mg/daily orally of conjugated equine estrogens and 2.5 or 5 mg/daily of medroxy progesterone acetate. No further specific treatment was prescribed. Mean duration of treatment was 9.82 (SD=5.42) years for all women; 9.70 (SD=5.44) in the younger group. Follow-up comprised 1815.84 woman-years, for 5 years or over (76.75%) on 142 women. Fifty-two women (28.11%) dropped out.
Results:
No deaths occurred during treatment. Four cardiovascular events (2.16%) were reported. No spontaneous bone fracture was documented. Nonetheless, there were 12 bone fractures of traumatic origin (6.48%), none of them hip fractures. Five breast cancers were observed. Likewise, one diagnosis of breast cancer for every 37 treated women from our series was evidenced. There were 117 women (63.24%) without any events.
Conclusion:
A higher risk of breast cancer or of serious cardiovascular events cannot be inferred from statistical analysis of 5 years or more of treatment.
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