Oestrogen has a wide:variety of roles beyond its involvement in the control and modulation of human fertility. The relative oestrogen deficiency experienced by women following the menopause leads to a wide range of symptoms and conditions, from the vasomotor effects of the climacteric to an increased risk of cardiovascular disease, bladder dysfunction, osteoporosis and possibly Alzheimer's disease. Most of these can be improved or at least modified by hormone replacement, therapy (HRT). Unfortunately, acceptance of HRT is poor, mainly due to the return to cyclic or unscheduled bleeding and the fear of breast cancer. Selective oestrogen receptor modulators (SERMs) are thus being developed with the goal of eliminating these unwanted effects on breast; and endometrium, while maintaining the benefits to the skeletal and cardiovascular systems. Raloxifene has received approval in the USA for osteoporosis prevention and others, such as Idoxifene and Droloxifene, are now in clinical trial. Unfortunately, they are not effective at treating the peri-menopausal vasomotor symptoms, and their effect on the central nervous system remains as yet unknown. However, Raloxifene is a major step towards the ideal goal of full receptor engagement in the non-reproductive tissues with concomitant non-engagement of the reproductive sites.
Beardsworth, S. A., Purdie, D. W., & Kearney, C. E. (1998). Selective oestrogen receptor modulation: An alternative to conventional oestrogen. Current Obstetrics and Gynaecology, 8(2), 96–101. https://doi.org/10.1016/S0957-5847(98)80022-X