The role of testicular biopsy in the investigation of male infertility.

Sixty-five testicular biopsies from infertile men were assessed retrospectively. In 21 patients infertility was attributed to varicoceles. In the remaining cases the testicular histology was classified into 3 major groups. Normal, hypospermatogenesis and germ cell aplasia. These histological categories were correlated with serum gonadotrophic hormone levels and sperm counts. All cases of germ cell aplasia showed azoospermia or severe oligospermia, but sperm counts alone were not reliable indicators of spermatogenesis. Patients with very low sperm counts and raised levels of serum FSH invariably had germ cell aplasia. These patients made up a group in whom testicular biopsies were of limited value in assessment. In all other instances the testicular biopsy was still an important tool in the assessment and prognostication for fertility in the subfertile male.