[Influence of primary hyperprolactinemia on human sexual behavior].

Eighty per cent of men with hyperprolactinaemia are impotent. Sexual deficiency, which for a long time is the only sign of the disease, is partly due to inhibition of testosterone secretion by high prolactin levels but also, probably, to reduced conversion of testosterone to dihydrotestosterone and, perhaps, to a direct effect of prolactin on the neurotransmitters involved in sexual activity. Eighty per cent of women with hyperprolactinaemia have reduced sexual drive and inability to reach orgasm; the underlying mechanisms are as yet unknown. In women, however, the initial symptoms are menstrual disorders. Most sexual disorders in both sexes regress after return to normal of plasma prolactin levels.