The necessity for bilateral biopsy in oligo- and azospermia.

The 384 testicles from 192 infertile men were examined by bilateral biopsy. The main reason of this investigation was to see whether differences in the varying degrees of damage to the seminal epithelium existed in both testicles. Depending on the damage, the material was divided into five groups. The conclusion is, that the greater the degree of damage, the greater are the differences in the findings in both testicles. The left testis was more often and more strongly damaged than the right.