#305 : Preparation of Epididymal/Testicular Spermatozoa; Technical Aspects and Its Impact on Success

Abstract

Background and Aims: The introduction of ICSI 30 years ago paved the way for epididymal/testicular spermatozoa to be used to fertilise oocytes in couples undergoing ART. Currently, spermatozoa is recovered from the epididymis or testis using varying approaches, including micro-surgery and fine-needle aspiration, mostly in men with obstructive and nonobstructive azoospermia. The samples delivered to the laboratory for processing are of varying quality with regards to amount of material/tissue, presence of spermatozoa, and other cells. The success of processing the tissue can have a direct impact on the outcome of the subsequent ICSI and our aim for this review was to identify ways to improve the preparation techniques for epididymal/testicular samples. Ethics approval was obtained from WSLHD HREC Ref 5583QA. Methods: The review included 527 ICSI cycles for 311 patients (2016-2022) where epididymal/testicular spermatozoa had been used. Approaches for sample preparation included mini-gradient centrifugation and removal of red blood cells using erythrocyte lysis buffer (ELB). In cases with severe oligoasthenozoospermia (105 cycles, 79 patients), a phosphodiesterase inhibitor (PI) was added to induce motility. Results: Employing mini-gradient centrifugation or adding ELB did not result in lost spermatozoa for any cases, but vastly reduced sample debris allowing for easier identification of spermatozoa. Fertilisation rate after ICSI was 57.9±1.2%. Motile spermatozoa were found and injected in all 105 samples after addition of PI and the fertilisation rate after ICSI was 55.3±2.7. To date cycles with PI have resulted in 26 live births with no abnormalities and all infants were of appropriate weight for gestational age. Conclusions: Employing precise preparation techniques for epididymal/testicular samples is paramount to allow for timely identification of motile spermatozoa for ICSI and assure optimal overall outcome. Sharing and discussing successful approaches with the wider embryology community allows for discussion and refining of techniques which can benefit all.