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Updated: May 24, 2026

Estrogen-Like Effect of Bazi Bushen Capsule in Ovariectomized Rats
Published on: April 7, 2023
[Selective Estrogen Receptor Modulators (SERMs) for prevention and treatment of postmenopausal osteoporosis]
1Prof. Emeritus für Gynäkologische Endokrinologie und Reproduktionsmedizin der Universitäts-Frauenklinik, Bern. martin.birkhaeuser@balcab.ch
Abstract:
The three modern Selective Estrogen Receptor Modulators (SERMs) Raloxifene, Lasoxifene and Bazedoxifene registered in Europe reduce in postmenopausal women with a high risk for osteoporosis the incidence of vertebral fractures by 30 - 50 %, depending on the subgroup they belong to. Solid prospective fracture data for risk reduction in non-vertebral fractures, including the hip, are missing for Raloxifene and Bazedoxifene. However, a post hoc analysis suggests that the risk for non-vertebral fractures is significantly reduced by Raloxfene in women with severe osteoporosis. The simultaneous decrease of the incidence of ER-positive invasive breast cancer in Raloxifene users is highly relevant for clinicians. Unfortunately, Raloxifene and Bazedoxifene are, in the EU and in Switzerland, only labelled for the use in the prevention and treatment of postmenopausal osteoporosis. SERMs may induce or augment vasomotor symptoms. Therefore, SERMs are not a first line therapy in early postmenopause. Looking at other hormonal options, Hormone Replacement Therapy (HRT) remains the first line therapy for fracture reduction in the peri- and early postmenopause. SERMs are an appropriate choice for the continuation of fracture prevention after an initial HRT, particularly for the prevention of vertebral fractures. SERMs are safe if (as in oral HRT) the slightly increased risk for venous thrombo-embolism is respected. In conclusion, SERMs have today their well established place in the prevention and treatment of postmenopausal osteoporosis, particularly in women with a simultaneously increased breast cancer risk.
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