Five infertile patients with polycystic ovarian disease were treated to induce ovulation with pure human urinary follicle-stimulating hormone and human menopausal gonadotropin consisting of follicle-stimulating hormone and luteinizing hormone in 1:1 ratio. No substantial differences were seen between the two types of treatment regarding plasma values of follicle-stimulating hormone, prolactin, testosterone, dihydrotestosterone, progesterone, and 17-hydroxypro-gesterone. Estrone, estradiol, and androstenedione values were higher during human urinary follicle-stimulating hormone treatments. Luteinizing hormone levels dropped in both treatments, but the fall was greater during human urinary follicle-stimulating hormone. No real differences were observed concerning number of ovulations, length of treatments, and follicle-stimulating hormone amounts administered; no hyperstimulations were observed. These data do not confirm the observation that more controlled responses of the ovaries can be elicited when low luteinizing hormone gonadotropin preparations are used.