[Hypogonadism with spermatogenesis (fertile eunuch syndrome) (author's transl)]

Hypogonadism with spermatogenesis (fertile eunuch syndrome) occupies a special nosologic situation because of it's clinical and paraclinical features. These include: eunuchism of testosterone's target tissues, contrasting with clinically normal testes; normal embryonic male differentiation; low serum testosterone concentrations; moderately decreased or normal LH serum concentrations which are coincident with low testosterone levels therefore reflecting at least relative LH insufficiency; normal FSH levels; normal LHRH response; variable clomifen response; poor spermatogenesis improved by HCG and/or testosterone, and in some cases by HMG; atrophic leydig cells. Although in very rare instances it may include anosmia, the fertile eunuch syndrome should be clearly distinguished from complete FSH and LH deficiency with or without anosmia. It must also be distinguished from the very uncommon isolated FSH deficiencies. The fertile eunuch syndrome probably originates in insufficient hypothalamic production of LHRH. The mechanism by which spermatogenesis is at least partly spared remains unknown.