Surgical sperm retrieval after previous vasectomy and failed reversal: clinical implications for in vitro fertilization.

OBJECTIVE

To investigate the effect of the interval between previous vasectomy reversal on retrieval rates of epididymal and testicular spermatozoa using percutaneous epididymal sperm aspiration (PESA), or testicular sperm extraction (TESE), and the subsequent reproductive potential of these gametes in intracytoplasmic sperm injection (ICSI) cycles.

PATIENTS AND METHODS

Sixty-six consecutive sperm retrievals were considered in patients who were azoospermic after previous vasectomy, of whom 54 had had a previous failed reversal, the remainder deciding against a reversal. PESA and TESE retrieval rates were noted, as were the time since vasectomy and the interval between vasectomy and unsuccessful reversal. The presence of palpable epididymal cysts was noted, with their effect on sperm retrieval rates. Fertilization and pregnancy rates were analysed in subsequent ICSI cycles using freshly retrieved spermatozoa or frozen-thawed cryopreserved spermatozoa.

RESULTS

All 66 patients had sperm retrieved successfully; the success rates for PESA were not significantly affected by previous failed reversal when compared with patients who had not had a reversal, at 14 of 54 (26%) vs five of 12 (P=0.3). The interval since vasectomy did not affect PESA retrieval rates but there was a significantly poorer retrieval rate for PESA in the presence of palpable epididymal cysts, at seven of 35 (20%) vs 12 of 23 (52%) (P=0.012). Fertilization rates were significantly lower using cryopreserved spermatozoa retrieved from either the epididymis or testis (50% vs 70%, P=0.007), although subsequent implantation and pregnancy rates were not significantly different.

CONCLUSION

Surgical sperm retrieval is successful in all cases of azoospermia secondary to vasectomy, either by PESA or TESE. There are no clinical markers to indicate which patients will have successful PESA after vasectomy, although the presence of epididymal cysts is associated with significantly lower retrieval rates. The reduction in fertilising ability of cryopreserved spermatozoa does not affect clinical pregnancy rates in ICSI cycles.