No differences in outcome after intracytoplasmic sperm injection with fresh or with frozen-thawed epididymal spermatozoa

This retrospective consecutive case series aimed at comparing the results o f intracytoplasmic sperm injection (ICSI) with fresh and with frozen-thawed epididymal spermatozoa obtained after microsurgical epididymal sperm aspir ation (MESA) in 162 couples, These couples were suffering from infertility because of congenital bilateral absence of the vas deferens (rt = 109), fai led microsurgical reversal for vasectomy or postinfectious epididymal obstr uction (n = 44), irreparable epididymal obstruction(n = 4), ejaculatory duc t obstruction (n = 2) or anejaculation (n = 3), Overall, 176 MESA procedure s were performed in the husbands, followed by 275 ICSI procedures with eith er fresh (n = 157) or frozen-thawed (It = 118) epididymal spermatozoa, No s ignificant differences were observed in the parameters of spermatozoa used either freshly or frozen-thawed, In the fresh epididymal sperm group 59.4% of all the injected oocytes fertilized normally as compared to 56.2% of all injected oocytes in the frozen-thawed epididymal sperm group, and embryoni c development was comparable between the two groups. A total of 245 transfe rs were performed: 145 after the use of fresh epididymal spermatozoa and 10 0 after the use of frozen-thawed spermatozoa, The overall pregnancy rate pe r ICSI cycle was significantly lower when frozen-thawed epididymal spermato zoa were used (26.3 versus 39.5%). However, no significant differences were found either in clinical and ongoing pregnancy rates or in implantation ra tes, There were no differences in pregnancy outcome, In patients suspected of having obstructive azoospermia with no work-up or an incomplete one, MES A is the preferred method for sperm recovery because a full scrotal explora tion can be performed and, whenever indicated, a vasoepididymostomy may be performed concomitantly, Recovery of epididymal spermatozoa for cryopreserv ation during a diagnostic procedure is certainly a valid option in these pa tients since ICSI may be performed later or even in another centre using th e frozen-thawed epididymal spermatozoa without jeopardizing the ICSI succes s rate.