From 1968 to 1972, a trial of a new agent, drostanolone propionate (Masteril), was conducted. This agent was tested against oophorectomy in a group of premenopausal patients, against nandrolone phenylpropionate (Durabolin) in a perimenopausal group, and against ethinyl oestradiol in a postmenopausal group. In the premenopausal group, 44% responded to Masteril and 22% to oophorectomy. In the perimenopausal group, 34,5% responded to Masteril and 39% to Durabolin. In the postmenopausal group, 57% responded to oestrogens and 38,5% to Masteril. The side-effects of Masteril are generally not serious and rarely contra-indicate its use. Masteril has been shown to be a useful and safe agent for all age groups, even though it may appear to be less effective than oestrogens in the postmenopausal patients.