The objective of this study was to examine the efficacy of D-triptorelin in the long protocol and follicle-stimulating hormone (FSH) in an IVF-embryo transfer program in a group of patients with polycystic ovary syndrome (PCOS) who had earlier failed to respond or did not conceive after clomiphene citrate (CC)/human menopausal gonadotropin (hMG) or 'flare up' gonadotropin-releasing hormone agonist (GnRHa)/hMG stimulation. Eighty-nine women with PCOS (based on typical ultrasound criteria) had 1-3 treatment cycles without success. The stimulation protocol was changed to D-triptorelin given in midluteal phase and when pituitary desensitization was achieved, FSH administration was started. The clinical pregnancy rate per transfer in this 'negatively selected' group of PCOS patients was 29%. This was the same as the rate for a group of women with tubal factor, as was the spontaneous miscarriage rate. Although the use of GnRH agonists in the long protocol increases the costs of treatment, the number of cancelled cycles is reduced. The pregnancy rate increased in this group of women with PCOS.