Analysis of spermatogenesis in non-obstructive azoospermic and virtually azoospermic men with known testicular pathology

It is widely thought that human testicles affected by unilateral pathology will have greater impairment of spermatogenesis than the otherwise unaffected testis. This study reviewed records of non-obstructive azoospermic (NOA) and virtually azoospermic (NOVA) men with associated testicular pathology who underwent testicular fine needle aspiration (FNA) mapping. Concentration of spermatozoa found in each testis was analysed to discern sperm-lateralization patterns in affected and unaffected testes. A total of 1098 FNA sites from 56 men (32 varicocele, 16 cryptorchidism, three epididymo-orchitis, two mumps orchitis, three torsion) were analysed. Overall, 38 patients (68%) had spermatozoa detected in at least one testis. Most men (68%) had equal proportions of FNA sites showing spermatozoa from both testes, 29% had more spermatozoa from the unaffected testis and 3% had more spermatozoa from the affected testis. Significantly fewer sperm-positive sites were observed on the affected (272 out of 752) than unaffected side (164 out of 346) (P < 0.0001, chi-squared test). When assessed by FNA mapping, most NOA and NOVA men with known unilateral testis pathology will have equal proportions of spermatozoa in both testes. However, when sperm production differs between sides, the unaffected side is much more likely to have spermatozoa. This information may be used to refine sperm-retrieval strategies in selected patients.