Progestogen therapy adverse effects

In 104 women with established postmenopausal osteoporosis, continuous estrogen + progestogen therapy resulted in increases in bone mineral density of the femoral neck and a fall in systolic blood pressure the most common adverse effects were mastalgia (44%) and vaginal bleeding (29%) (2). 

Tibolone is an agonist at estrogen and progestogen receptors, with weak androgenic activity. It is given as an alternative to hormone replacement therapy, without added progestogen, and has been in use for some 30 years to treat bone loss in post-menopausal women. Some long-term studies (for example over 10 years) appear to have confirmed its safety and relative freedom from adverse effects (1). In particular there is little or no increase in thrombotic events and the incidence of breast tenderness is low. 

Cerin A, Heldaas K, Moeller BThe Scandinavian LongCycle Study Group. Adverse endometrial effects of long-cycle estrogen and progestogen replacement therapy. N Engl J Med 1996 334(10) 668-9. 

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