Hormonal parameters in incidental varicoceles and those causing infertility.

The gonadotropin responses to a 4-hour infusion of gonadotropin-releasing hormone (GnRH), the prolactin (PRL) responses to a bolus injection of thyrotropin-releasing hormone (TRH), and seminal plasma dihydrotestosterone (DHT) levels were assessed before and 6 to 12 months after varicocelectomy was performed in 56 infertile men with varicoceles and sperm densities less than 30 X 10(6)/ml. The men were divided into four groups, determined by their sperm densities and hormonal parameters. Groups I (18 men) and II (12 men) had sperm densities less than 10 X 10(6)/ml, and groups III (16 men) and IV (10 men) had sperm densities of 11 to 30 X 10(6)/ml. The men from groups I and III had excessive preoperative gonadotropin and PRL responses, and lower-than-normal seminal plasma DHT levels. The men in groups II and IV had normal hormonal values. After operation, 12 of the men from group I and 11 from group II had improvements in seminal and hormonal parameters. The other men in these two groups and all of the men in groups II and IV had no changes in seminal and hormonal parameters after operation. This study indicates that an assessment of these hormonal parameters may be useful in predicting which men with varicoceles are likely to have an improvement in sperm density after varicocele repair.

Hormonal parameters of men with varicoceles before and after varicocelectomy.

The gonadotropin responses to a 4-hour infusion of gonadotropin-releasing hormone (GnRH) and seminal plasma dihydrotestosterone (DHT) and testosterone levels were assessed before and 6 to 12 months after varicocelectomy in 22 men with varicoceles. Twelve men were severely oligozoospermic (sperm densities less than 10 X 10(6)/ml), whereas 10 men had sperm densities between 11 and 30 X 10(6)/ml. Each man had excessive gonadotropin responses to GnRH and lower than normal seminal plasma DHT levels preoperatively. Eight of the 12 severely oligozoospermic men and 6 of the other 10 men had postoperative improvements in sperm density. These men (responders) had normalization of gonadotropin response and seminal plasma DHT levels. The nonresponders had identical hormonal parameters before and after surgery. These results indicate that the pantesticular defect in hormonal synthesis and spermatogenesis, seen in some men with varicoceles, can be reversible.

Seminal plasma testosterone and dihydrotestosterone levels in men with varicoceles.

Testosterone (T) and dihydrotestosterone (DHT) were measured in the seminal plasma of men with varicoceles, azoospermic vasectomized men and men with normal seminal parameters. Testosterone levels were not different significantly in these groups of men. DHT concentrations and the DHT/T ratio were significantly lower than normal in men with varicoceles and sperm densities below 30 million/ml and the vasectomized men, but not different from normal in the men with varicoceles whose sperm densities were greater than 30 million/ml. In men whose sperm density and/or motility improved after varicocelectomy, there was an increase in seminal plasma DHT levels and the DHT/T ratio. When seminal parameters were not improved by varicocelectomy, there was no change in DHT levels or in the DHT/T ratio. It is concluded that men with varicoceles and sperm densities below 30 million/ml have a deficiency in the epididymal 5 alpha-reduction of testosterone.

The gonadotropin response of men with varicoceles to a four-hour infusion of gonadotropin-releasing hormone.

The serum gonadotropin, testosterone, and estradiol responses to a 4-hour intravenous infusion of gonadotropin-releasing hormone (GnRH) were studied in four groups of men: severely oligospermic men with varicoceles and sperm densities less than 1 X 10(7)/ml, men with varicoceles and sperm densities between 1.1 X 10(7) and 3 X 10(7)/ml, men with varicoceles and sperm densities greater than 3 X 10(7)/ml, and men of normal fertility. Each group had similar preinfusion luteinizing hormone (LH), follicle-stimulating hormone (FSH), testosterone, and estradiol levels. Both the severely oligospermic men and the men with sperm densities between 1.1 X 10(7)/ml and 3 X 10(7)/ml had excessive gonadotropin responses to the GnRH infusion. The gonadotropin responses of the men with sperm densities greater than 3 X 10(7)/ml were not different from normal. These results demonstrate that men with varicoceles and sperm densities less than 3 X 10(7)/ml have an altered integrity of their hypothalamic-pituitary-testicular axes, which can be demonstrated by their responses to GnRH.