Follicle stimulating hormone (FSH) and interstitial cell stimulating hormone (ICSH) in relation to gametic output in 643 males.

Abstract

ABSTRACT The relation between gonadotrophin secretion and average gametic output has been investigated in 643 healthy male partners of barren couples. FSH and ICSH excretion in urine were determined by means of bioassay and radioimmunoassay respectively, and FSH in serum was determined by radioimmunoassay. The mean sperm counts were calculated for each patient from serial seminal analyses over a 12 week observation period. The subjects were grouped according to their average gametic output and statistically significant differences were found between all mean excretion values for FSH, and for all but one pair of ICSH mean excretion values, when groups of patients with decreasing gametic output were compared. Individual assay results were, however, widely spread within each subgroup with extensive overlapping between the groups. A general trend towards an increase in FSH as well as of ICSH secretion with decreasing gametic output was found. Thus, the mean excretion of FSH was found to be increased by 2.7 times, and the mean excretion of ICSH by 1.7 times, when azoospermic males were compared with males with a mean sperm count of 20 mill, per ml or more. There was no evidence of accumulation of males with low or absent gonadotrophin secretion in any subgroup, and this may indicate that only few, if any, of the ordinary healthy male partners in the present couples suffered from a primary pituitary failure to secrete FSH or ICSH. About 50 per cent of the males with increased FSH secretion and low or absent gametic output may have a selective spermatogenic failure, while the remainders are likely to suffer from a more general gonadal deficiency, since they also have a concomitant rise in ICSH.