Testicular Spermatozoa Are of Better Quality Than Epididymal Spermatozoa in Patients With Obstructive Azoospermia

Objective: To assess sperm quality as a function of the sampling site (testis or epididymis) in obstructive azoospermia (OA).

Materials and methods: DNA fragmentation rates in spermatozoa sampled from the testis and epididymis (from patients with different etiologies of OA) were assessed in a dUTP nick-end labeling assay.

Results: Twenty-one OA patients were included: 5 had congenital bilateral absence of the vas deferens, 8 had genital tract infections, and 8 had idiopathic OA. A total of 8506 spermatozoa sampled from the testis, 18,358 sampled from the caput epididymis, and 18,881 sampled from the corpus/cauda epididymis were assessed. For each patient, spermatozoa from the testis had a lower overall DNA fragmentation rate (6.71% ± 0.75 in average) than epididymal spermatozoa from the caput (14.86% ± 1.89 in average; P = .0007) or the corpus/cauda (32.61% ± 3.11 in average; P < .0001). The DNA fragmentation rates did not differ significantly as a function of the etiology of OA. In this small series, all deliveries were obtained with sperm samples with a low DNA fragmentation rate and delivery rates tended to be higher when testicular sperm (rather than epididymal sperm) was used (35.7% vs 12.1%, respectively; P = .06).

Conclusion: Our data argue in favor of using testicular sperm (rather than epididymal sperm) for patients with obstructive azoospermia.