[Estimation of FSH and LH before and after stimulation with LH-RH in male sterility and hypogonadism].

Plasma levels of FSH and LH, in 232 subjects examined for sterility or hypogonadism, have been assessed vefore and after stimulation by LH RH (100 microng IV). In excretory azoospermia, the basal levels as well as the response to LH RH of FSH as well as LH are normal. In early testicular damage (constitutional or acquired); basal FSH levels are elevated (91% of the cases) as well as the FSH response to LH RH (78%); basal LH levels are either normal (66% of the cases) or elevated (34%). An augmentation of the LH response has been found in 92% of the cases. In hypogonadotrophic hypogonadism (n = 12) 3 types of responses have been noticed : absence of response of FSH and of LH (7 cases); normal FSH response, no LH response (2 cases); exaggerated FSH and LH response (2 cases). In idiopahtic oligospermia (n = 84); basal FSH levels are elevated in 24 cases but normal in the rest. There is a highly significant correlation between basal FSH and its response to LH RH injection (r = 0.73, t = 9,67 p less than 0,001); basal LH levels are normal, except in 5 cases where a definite increase has been noted. The response of LH is exaggerated in 36 cases which includes the 5 showing enhanced basal LH levels. There is a highly significant correlation between FSH response and LH response (r = 0,55; t = 5,94; p less than 0,001). Exploration of patients with varicocoele intact or operated show no difference from those suffering from idiopathic oligospermia. From a practical point of view, the LH RH test enables : a distinction between excretory azoospermia and secretory azoospermia with normal testicular volume, without recourse to testicular biopsy; affirmation, in 36% of cases with idiopathic oligospermia of the early damage to spermatogenesis, thus contra-indicating any treatment involving testicular stimulation. From the physico-pathological point of view : the early damage to spermatogenesis is characterized by an elevation in basal FSH and its response to LH RH injection. The significance of the augmented Lh response, which often accompanies an augmentation in FSH response but incertain cases is isolated, is discussed.