PRL and Infertility: In protocols for ovarian stimulation for the treatment of infertility, gonadotropin-releasing hormone (GnRH) agonist analog has been used as an alternative to human chorionic gonadotropin for triggering ovulation.1 Administration of the analog at the preovulatory phase induces an endogenous surge of luteinizing hormone (LH) and follicle-stimulating hormone (FSH), and the effect may be more physiological than that of exogenous human chorionic gonadotropin.2 This study was designed to investigate whether the pattern of prolactin secretion is also affected by the administration of GnRH-agonist.