Osteoporosis, oestrogens and oöphorectomy. A proposed new test of oestrogenic potency.

The role of oestrogens, endogenous and exogenous, in the pathogenesis of osteoporis is briefly reviewed. Aspects of research into effects of oestrogens on plasma calcium and phosphorus metabolism, conducted at Groote Schuur Hospital, are incorporated in the discussion. The current role of oestrogen therapy in the prevention of osteoporosis is presented. Evidence suggests that different oestrogenic substances produce different metabolic effects. On this basis a new test for assessment of oestrogenic potency is proposed. It is concluded that appropriate or specific oestrogens are of value in the prevention of osteoporosis, but play little or no role once the process is fully developed. A positive preventive measure recommended is conservatism with regard to ovaries during gynaecological operation on young women.