Antipsychotics affect fertility through changes in prolactin level as the typical antipsychotics are regarded as the most common medications related to hyperprolactinaemia. They lead to acute and persistent increase of prolactin levels and thus affecting hormonal balance.
The great response of prolactin in women of a reproductive age, who are not nursing or pregnant, leads to the inhibition of the normal pulsatile secretion of gonadotropin-releasing hormone (GnRH) of the hypothalamus. These, not so frequent, pulses of GnRH result in regular menses, on the one hand, but impaired follicular growth on the other. Greater impairment of pulsatile GnRH secretion leads to an anovulatory stage with menses being too frequent, too heavy, or infrequent (amenorrhea). If the release of the egg is compromised, sperm can not be encountered and fertilization does not occur.
Further restraining of pulsatile GnRH secretion provokes deficient secretion of luteinizing hormone (LH) and follicle-stimulating hormone (FSH), in amounts not adequate to induce a proper ovarian response (the ability to recruit adequate follicles). That provokes a hypoestrogenized amenorrheic cycle and side reactions of estrogen deficiency - comparable to what occurs during menopause or infertility. Hence, as hyperprolactinaemia is associated with estrogen suppression, the initial prolactin elevation is clinically identified by reproductively related symptoms, primarily in females.
Even in men, antipsychotic medication can lead to infertity. No sperm could be present in the ejaculate (azoospermia). Likewise, men could suffer from difficulty maintaining an erection and decreased sexual desire.