Serum luteinzing hormone pulsatility and intratesticular testosterone and oestradiol concentrations in idiopathic infertile men with high and normal fofficle stimulating hormone serum concentrations

The purpose of the study was to evaluate pulsatile luteinizinghormone (L release and intratesticular concentrations of testosteroneand oestradlol in infertile men, to determine if alterationsin gonadotrophin secretion are associated with changes in thetesticular concentrations of steroids. Patients with idiopathicoligo/azoospermia were divided into a high follicle stimulatinghormone (FSH) group (n=5) and a normal FSH group (n = 6). Bloodsamples were taken every 15 mm for 6 h to determine LH, FSH,testosterone, oestradiol, sex hormone binding globulin, bioactiveLH and bioavailable testosterone. The patients underwent a bilateraltesticular biopsy for histological assessment and to determinetestosterone and oestradiol concentrations. Serum measure mentswere compared with those of seven fertile men. The high FSHgroup had a higher concentration of serum UI and oestradiolthan normal men (P < 0.01) and showed a lower frequency ofLII pulses than the normal FSH group and control men (P <0.01). Intratesticular oestradiol was higher in the high FSHgroup (P < 0.001), with a lower testosterone/oestradlol ratio(P < 0.01). Patients showed a negative correlation betweenthe serum testosterone/LH ratio and FSH (r = -–0.75; P< 0.01) and a positive correlation between the testicularoestradiol concentration and serum FSH (r=0.86; P<0.01).The histopathological examination only showed a smaller tubediameter in the high FSll group (P < 0.05). These data seemto indicate that a higher intratesticular concentration of oestradiolwith a lower testosterone/oestradiol ratio in the high FSH groupcould have a deleterious effect on spermatogenesis.