Morphological changes of spermatozoa in proximal vas deferens after vasectomy

Aim: To investigate the morphological changes of spermatozoa in the proximal vas deferens after vasectomy.Methods: Proximal vas deferens fluids were collected from 79 fertile men (group A) and 64 vasectomized men (groupB) during the operations of vasectomy or vasovasostomy. Sperm morphology in the proximal vas deferens wasanalyzed after staining with the modified Papanicolaou method. Results: The percentage of spermatozoa with anormal oval head from group B (50.7 % ± 21.7 % ) was significantly lower than that of group A (75.2 % ±11.1%). The data in group A was similar to those of normal semen and therefore represents the physiologicalcondition of the proximal vas deferens sperm of fertile men. There were no significant differences in the percentages ofnormal oval heads in group B with the time since vasectomy. Conclusion: After vasectomy, the spermatozoa in theproximal vas deferens and epididymis were continuously degenerating and being replenished by spermatozoa comingfrom testis. The obvious morphological degeneration occurred in the sperm tail and spermatozoa with a small oval headand amorphous heads were increased.