Use of Testicular Sperm for ICSI: Pro

Abstract

Spermatozoa retrieved from the testis of men with high levels of seminal sperm DNA fragmentation (SDF) tend to have better DNA quality. Given the negative impact of SDF on assisted reproductive technology (ART) outcomes, an increased interest has emerged about the use of testicular sperm for intracytoplasmic sperm injection (TESTI-ICSI). In this chapter, we used a SWOT (strengths, weaknesses, opportunities, and threats) analysis to summarize the advantages and drawbacks of this type of intervention. The rationale of using TESTI-ICSI is to bypass post-testicular induced DNA fragmentation that occurs mainly by reactive oxygen species (ROS) during sperm transport through the epididymis. As a matter of fact, testicular sperm are shown to have three- to fivefold lower DNA fragmentation than ejaculated sperm. The strength of this method is to maximize oocyte fertilization by genomically intact testicular spermatozoa and to increase the chances of creating a normal embryonic genome and the likelihood of live birth, as recently demonstrated. The weaknesses are the limited evidence available and the invasiveness of sperm retrieval, which has potential complications. However, ample opportunities exist to investigate the effectiveness of TESTI-ICSI in other patient subsets, including cryptozoospermia, repeated implantation failure, and repeated miscarriage, as well as to compare TESTI-ICSI to other laboratory preparation methods used to deselect sperm with damaged DNA. Lastly, the threats relate to the possibility of using testicular sperm with putative deficiencies that would be blocked in its ontogeny during the maturation process. In conclusion, current data indicate that the use of testicular sperm is associated with improved ICSI outcomes in men with oligozoospermia and high SDF. Testicular sperm retrieval should be considered when performing ICSI in such cases, provided less invasive treatments for alleviating DNA damage have failed. A call for continuous monitoring is nonetheless required until the safety of this strategy to the health of offspring is confirmed.