To determine the efficacy and safety of phytoestrogens for the treatment of osteoporosis in postmenopausal women.

In particular, the principal objective of this review is to reliably answer the two following questions:

1) Are phytoestrogens effective in preventing bone fractures when administered in postmenopausal women?

2) Are phytoestrogens safe in terms of adverse events for the treatment of osteoporosis in postmenopausal women?

Secondary objectives are to determine the efficacy and safety of phytoestrogens in the following subgroups:

1) Early postmenopausal women (less than 35 years old)

2) Women who have sustained a fracture.