SERUM LUTEINIZING-HORMONE PULSATILITY AND INTRATESTICULAR TESTOSTERONE AND ESTRADIOL CONCENTRATIONS IN IDIOPATHIC INFERTILE MEN WITH HIGH AND NORMAL FOLLICLE-STIMULATING-HORMONE SERUM CONCENTRATIONS

The purpose of the study was to evaluate pulsatile luteinizing hormone (LH) release and intratesticular concentrations of testosterone and o estradiol in infertile men, to determine if alterations in gonadotroph in secretion are associated with changes in the testicular concentrati ons of steroids. Patients with idiopathic oligo/azoospermia were divid ed into a high follicle stimulating hormone (FSH) group (n = 5) and a normal FSH group (n = 6). Blood samples were taken every 15 min for 6 h to determine LH, FSH, testosterone, oestradiol, sex hormone binding globulin, bioactive LH and bioavailable testosterone. The patients und erwent a bilateral testicular biopsy for histological assessment and t o determine testosterone and oestradiol concentrations. Serum measurem ents were compared with those of seven fertile men. The high FSH group had a higher concentration of serum LH and oestradiol than normal men (P < 0.01) and showed a lower frequency of LH pulses than the normal FSH group and control men (P < 0.01). Intratesticular oestradiol was h igher in the high FSH group (P < 0.001), with a lower testosterone/oes tradiol ratio (P < 0.01). Patients showed a negative correlation betwe en the serum testosterone/LH ratio and FSH (r = -0.75; P < 0.01) and a positive correlation between the testicular oestradiol concentration and serum FSH (r = 0.86; P < 0.01). The histopathological examination only showed a smaller tube diameter in the high FSH group (P < 0.05). These data seem to indicate that a higher intratesticular concentratio n of oestradiol with a lower testosterone/oestradiol ratio in the high FSH group could have a deleterious effect on spermatogenesis.