Studies of percutaneous epididymal sperm aspiration (PESA) and intracytoplasmic sperm injection

Four distinct studies were carried out using two data sets ofpercutaneous epididymal sperm aspiration (PESA) and intracytoplasmicsperm injection (ICSI) procedures performed from March 1993to January 1997. In study A, an analysis of 181 ICSI treatmentcycles following PESA revealed a successful epididymal spermretrieval rate of 83%. It confirmed that PESA is an effectivesperm retrieval method and the associated ICSI pregnancy rate(35% per embryo transfer) compared favourably with that of othersperm retrieval methods. In study B, the relevance of a priordiagnostic PESA procedure was ascertained by comparing the spermretrieval rates in two groups of patients having their firstICSI treatment cycle with spermatozoa retrieved through PESA.Group B1 (n=50) had diagnostic PESA prior to the ICSI treatmentcycle PESA procedure, unlike patients in group B2 (n=64) whodid not. The sperm retrieval rate in the treatment cycle procedurewas not different at 90 and 82.8% for groups B1 and B2 respectively.However, the discontinuation of diagnostic PESA is fraught withproblems including liability to medico-legal sanctions. In studyC, analysis of 177 treatment cycles involving PESA and ICSIrevealed a successful sperm retrieval rate by PESA of 82% inthe first cycle, 93% in the second, 96% in the third and 100%in the fourth cycle. The same trend was evident when sperm retrievalwas examined in relation to each of the epididymides. Retrievedspermatozoa were found to be motile in 67-100% of cases andthe frequency of samples containing motile spermatozoa did notdecrease with increase in the number of PESA attempts. Theseresults show that PESA does not jeopardize future epididymalsperm retrieval. In study D, the outcome of treatment with ICSIusing ejaculated spermatozoa (305 cycles) (group D1) was comparedwith that of ICSI using spermatozoa obtained through PESA (54cycles) (group D2). The median age of women in the two groupsof couples was similar (34 years). In group D1, 70% of metaphaseII oocytes were fertilized compared with 61% in group D2 (P<0.01).The cleavage rate and the median numbers of transferred andcryopreserved embryos were similar in both groups. There wasno significant difference between the clinical pregnancy rates(33 and 42% in groups D1 and D2 respectively). Our results showthat the outcome of PESA-ICSI treatment compared favourablywith that of ICSI using ejaculated spermatozoa.