A possible relationship between prolactin and spermatogenesis in humans

In order to investigate the effect of prolactin on spermatogenesis, we studied 205 consecutive male patients in whom 121 were normozoospermic (counts greater than 20 x 10(6)/ml), 62 were oligozoospermic (counts less than 20 x 10(6)/ml), and 22 were azoospermic. We compared prolactin with semen analysis. There was an increased incidence of high prolactin levels in the oligozoospermic and azoospermic group of patients. We noted an increase in the number of morphologically normal spermatozoa within the hyperprolactinaemic groups of patients. This may suggest that prolactin plays a regulatory role in spermatogenesis.