Combined oestrogen-gestagen preparations were applied to 169 women who had been sterile for an average period of 2.5 years, between 1975 and 1979. Their uncorrected pregnancy rate was 19 per cent. Pregnancy rates were 25 per cent for women who desired to have children up to two years or six per cent for those who tried longer. Oestrogen-gestagen therapy was successful in 20 per cent of women up to 30, but only in nine per cent of those beyond that age limit. Best therapeutic results were 45 per cent in cases of secondary amenorrhoea and 35 per cent in cases of genuine corpus luteum insufficiency. Anovulation, disorders of menstrual regularity, and Stein-Leventhal syndrome proved to be unfavourable conditions for this kind of therapy. The course of pregnancy was not accompanied by peculiarities of extraordinary dimensions. Combined oestrogen-gestagen treatment was found to be an appropriate initial therapy, within WHO Group II, for secondary (post-pill) amenorrhoea and corpus luteum insufficiency. While the presence of additional sterility factors does not necessarily mean contra-indication, prospects of success are reduced.