Repeated microdissection testicular sperm extraction in patients with non-obstructive azoospermia: Outcome and predictive factors

OBJECTIVE: To assess the feasibility of repeated sperm recovery in patients with non-obstructive azoospermia (NOA), as little is known about the extraction rate in repeated microdissection testicular sperm extraction (microTESE) in these patients. PATIENTS AND METHODS: A total of 134 men with NOA had their first sperm recovery between January 2013 and February 2020. Repeated microTESE had been done mostly for patients with a successful initial retrieval. RESULTS: In the 323 procedures performed on the 134 men with NOA, sperm could be retrieved in 236 procedures (73.1%). A total of 88, 61 and 40 men underwent two, three and four sperm retrievals, respectively. In these cycles, sperm could be extracted in 65 (73.9%), 53 (86.9%) and 37 (92.5%) men, respectively. During the first microTESE procedure, sperm could be extracted in 81 (60.4%) men with NOA. In all, the success rate was significantly different between subgroups, showing highest rate in hypospermatogenesis cases (95.6%), followed by maturation arrest (58.5%), and Sertoli cell-only syndrome (56.0%). However, this difference was not significant at the third and fourth repeated microTESE. The FSH levels and testicular volume were among the noticeable factors affecting success of sperm retrieval. The duration between the first and second biopsies significantly increased the success rate by a factor of 1.3-fold/month; however, afterwards, the duration did not play any role in the success of microTESE. The success of previous trial significantly increased the probability of success by 10.1-fold in the second trial, 5.6-fold in the third trial, and 16.5 folds in the fourth. CONCLUSION: Repeated MD -TESE ensures a high sperm recovery rate in patients with NOA. These data also show that when no spermatozoa can be obtained after thawing cryopreserved testicular sperm for ICSI in NOA patients, a repeat microTESE procedure can be planned. ABBREVIATIONS: ICSI: intracytoplasmic sperm injection; IVF: in vitro fertilisation; MA: maturation arrest; (N)OA: (non-)obstructive azoospermia; OR: odds ratio; SCOS, Sertoli cell-only syndrome; SRR: spermatozoa retrieval rate; (micro)TESE: (microdissection) testicular sperm extraction