Related Experiment Video
Updated: Aug 23, 2026
An In Vivo Estrogen Deficiency Mouse Model for Screening Exogenous Estrogen Treatments of Cardiovascular Dysfunction After Menopause
Published on: August 13, 2019
[Effects of hormonal replacement therapy on breast density in postmenopausal women]
T Bisanti1, A P Cavalieri, O Capri
1Dipartimento di Scienze Ginecologiche, Perinatologia, Puericultura, Università degli Studi di Roma La Sapienza, Roma, Italy.
Aim:
Recent studies have indicated that conventional hormonal replacement therapy (HRT) is associated with an increase in breast density. The aim of this non randomised prospective study was to evaluate the effects of HRT and Tibolone on breast density in postmenopausal women.
Methods:
The study population included 41 healthy women, who were on different HRT regimens and completed their 5-year mammographic follow-up. Before starting HRT, a baseline mammography was performed and repeated at 12-month interval during the follow-up. The patients, 41 healthy postmenopausal women, received 2 different treatments: continuous transdermal estrogen 50 microg/day plus sequential MPA 10 mg/day for 12 days at cycle (21 patients), Tibolone 2.5 mg/day (20 patients).
Results:
An increase in breast density was present in 25% of women receiving estrogen plus MPA. There was no mammographic breast density increase in Tibolone group; 9.5% of women receiving Tibolone showed reduced breast density. The modifications of breast density were reported during the 1st year of therapy.
Conclusion:
These findings show that different HRT regimens have different effects on breast density. Tibolone does not significantly affect breast density, so it may be a preferable therapy for a larger group of postmenopausal women, including those with a familiar history of breast cancer and those with breast density.
Related Concept Videos
01:29Bone Disorders
Bone deposition is also affected by the levels of sex hormones like estrogen and testosterone that promote osteoblast activity and bone matrix synthesis. When the level of these hormones decreases due to aging, it causes a reduction in bone deposition. As a result, bone resorption by osteoclasts...
01:28Menopause
01:40Bone Remodeling
01:22Target Cell Response to Hormones
Notably, the cellular response can be regulated by altering the number of receptors expressed in the cell. For example, prolonged exposure to elevated hormone levels results in a gradual decline or down-regulation in the number of receptors for that specific hormone on the cell surface. Conversely, in response to low hormone levels, cells may use up-regulation, producing an...
01:22Hormonal Regulation of the Menstrual Cycle
At puberty, GnRH begins a pulsatile release pattern, which triggers the anterior pituitary gland to secrete follicle-stimulating hormone (FSH) and luteinizing hormone (LH). The frequency and amplitude of GnRH pulses vary across the menstrual cycle, with faster pulses favoring LH release and slower pulses favoring FSH release.
01:24Disorders of the Female Reproductive System