New indication of testis biopsy for azoospermia: a clinical study in Japanese patients

Because of the progress made with assisted reproductive techniques, we decided to clarify the indication for testis biopsy in Japanese azoospermic patients. A total of 88 azoospermic patients were recruited with testis histologies obtained by bilateral biopsy. Testicular histology was evaluated using Johnsen's score count. Patients with at least 1 testis containing sperm were assigned to the active spermatogenesis group. Patients whose testes had no sperm were assigned to the hypospermatogenesis group. Differences in terms of the clinical data between the 2 groups were analyzed. Clinical data consisted of past history, physical examination and hormone concentrations. The unpaired t test was generally used to examine the statistical significance of any differences between the 2 groups. 1) There were significant differences between the 2 groups in the levels of serum testosterone and luteinizing hormone. 2) There were markedly significant differences between the 2 groups in terms of testis volume and the concentration of serum follicle-stimulating hormone (FSH). 3) The smallest testis volume and the highest serum FSH value in the active spermatogenesis group were 7 ml and 32.7 mlU/ml (normal range 2.9-8.2), respectively. In conclusion, although the presence or absence of active spermatogenesis can be accurately predicted by measuring the testis volume and serum FSH, testis biopsy should be carried out in patients with a testis volume greater than 7 ml or a serum FSH less than 4 times normal when the use of assisted reproductive techniques are planned.