Menotropins are appropriate for patients lacking endogenous gonadotropins or for patients having ovaries capable of a normal response. This report is based upon computer tabulations of pooled data abstracted from 510 patients to whom 1897 treatment cycles with menotropins were administered during the last 15 years. The results of treatment are based upon detailed analyses in different groups of patients to whom the same gonadotropin preparation was administered according to a similar treatment schedule. The percentage of patients who conceived following therapy (the pregnancy rate) in group I (women with negligible endogenous estrogen activity and low gonadotropin levels) was 60.4%; in group II (women with normal gonadotropin levels and distinct endogenous estrogen activity in whom all other treatments had failed) the pregnancy rate was 21.4%. The success rates (the percentages of women who took home at least one living child) were 52.1% in group I and 14.5% in group II. Altogether, 250 children were born to 184 women who conceived following treatment. The mean numbers of treatment cycles per patient were 3.69 in group I and 3.24 in group II. Among women of group I who conceived, 94.1% did so within four treatment cycles and of group II patients 95.2% did so within six treatment cycles. The over-all mild hyperstimulation rate was 4.26% and the severe hyperstimulation rate was 0.36%. The over-all multiple pregnancy rate was 32.5%.