How successful is TESE-ICSI in couples with non-obstructive azoospermia?

STUDY QUESTION: What are the chances of a couple with infertility due to non-obstructive azoospermia (NOA) having their genetically own child by testicular sperm extraction combined with ICSI (TESE-ICSI)? SUMMARY ANSWER: Candidate TESE-ICSI patients with NOA should be counselled that, when followed-up longitudinally, only a minority (13.4%) of men embarking for TESE eventually become a biological father. WHAT IS KNOWN ALREADY: Data available in the literature are only fragmentary because they report either on sperm retrieval rates after TESE or on the outcome of ICSI once testicular spermatozoa has been obtained, mostly in a selected subpopulation. Unfortunately, reliable data to counsel men with NOA on their chance to become a biological father are still lacking. STUDY DESIGN, SIZE, DURATION: This is a retrospective cohort study performed in the Centre for Reproductive Medicine, University Hospital of Brussel, approved by the institutional review board of the hospital. PARTICIPANTS/MATERIALS, SETTING AND METHODS: We identified all patients with NOA, based on histology, who had their first testicular biopsy between 1994 and 2009. Patients were followed longitudinally during consecutive ICSI cycles with testicular sperm. The primary outcome measure was live birth delivery. The cumulative live birth delivery rate was calculated, based only on ICSI cycles with testicular sperm (fresh and/or frozen) available for injection. When patients delivered after transfer of supernumerary frozen embryos, this delivery was tallied up to the (unsuccessful) original fresh ICSI cycle. The sperm retrieval rate and pregnancy rate were secondary outcome measures. MAIN RESULTS AND THE ROLE OF CHANCE: Among the 714 men with NOA, 40.5% had successful sperm retrieval at their first TESE. In total, 261 couples had 444 ICSI cycles and 48 frozen embryo transfer cycles, leading to 129 pregnancies and 96 live birth deliveries. Crude and expected cumulative delivery rates after six ICSI cycles were 37 and 78%. LIMITATIONS AND REASON FOR CAUTION: A retrospective cohort study design was the only way to study the cumulative delivery rate after TESE-ICSI in couples with NOA. Intrinsic limitations are related to the observational study design. WIDER IMPLICATION OF THE FINDING: TESE-ICSI is a breakthrough in the treatment of infertility due to NOA, with almost 4 out of 10 (37%) couples having ICSI obtaining a delivery. However, unselected candidate NOA patients should be counselled, before undergoing TESE, that only one out of seven men (13.4%) eventually father their genetically own child. STUDY FUNDING AND COMPETING INTERESTS: None declared.