Nine women with chronic anovulation caused by polycystic ovarian disease, which was unresponsive to clomiphene citrate therapy, were given a gonadotropin-releasing hormone agonist (buserelin) to induce pituitary desensitization. After 4 weeks induction of ovulation was attempted with a step-up administration of urinary follicle-stimulating hormone. Buserelin treatment was discontinued only in the presence of a positive pregnancy test result. Different responses were observed between the first and subsequent cycles. Whereas estradiol production and follicular growth were closely correlated in the first attempt, we recorded a dissociation between these two parameters of ovarian response during subsequent stimulations. Four clinical pregnancies occurred in these nine patients, and there was one abortion. This therapeutic approach can be successfully used to induce ovulation; however, prolonging pituitary suppression between treatment cycles changes the type of ovarian response and is not followed by better results.