Implication of sperm processing during assisted reproduction on sperm DNA integrity

tau.amegroups.com © Translational Andrology and Urology. All rights reserved. The authors (Drs. Borini, Tarozzi and Nadalini), in their invited commentary (1) in response to the practice recommendations by Agarwal et al. (2), raised several valid arguments about sperm DNA fragmentation (SDF) testing. In our response to Borini et al., we intend to share additional information on SDF for the readers to enrich this ongoing discussion. A number of guidelines from various professional societies are currently available concerning evaluation of infertile male patients. The Practice Committee of the American Society of Reproductive Medicine (ASRM) published a clinical practice guideline on the value of SDF testing in 2015 (3). The Committee Opinion does not recommend the routine use of SDF based on the limited data which underlines the relationship between abnormal DNA integrity and reproductive outcomes. However, the more important message from the Committee Opinion is that the effect of abnormal SDF on the results of intrauterine insemination (IUI)/in vitro fertilization (IVF)/ intracytoplasmic sperm injection (ICSI) is evident in view of the expanding literature on the topic. Actually, we agree with the ASRM guideline that states the low predictive ability of SDF testing alone on assisted reproductive technology (ART) outcomes in the context of a complex reproductive system in human. It is unlikely that the result of dynamic interaction among multiple confounding factors, both in natural conception and ART, can be confirmed by a single test. This is the main reason for practice recommendations (2), as proposed by Agarwal et al., in establishing the role of SDF tests clinically based on the best available evidence. We believe that the observation from a wider application of the test clinically, particularly in the scenarios suggested in the practice recommendations but not limited to it, will improve our understanding in selected utilization of SDF tests in suitable patients in a cost-effective manner. Borini et al. highlighted important limitations of SDF tests, such as the lack of standardization and different nature of SDF detected by various methods. But it is also prudent to recognize the efforts from various researchers worldwide in response to the pitfalls of SDF tests over recent years. There are numerous studies in the literature comparing various SDF tests (4). The results of these assays are generally not comparable due to the different aspects of SDF measured, as mentioned by the authors. Nonetheless, the tests are interrelated to a greater or lesser extent by reflecting the overall quality of the specimen and the properties of the sperm DNA, and may point to a common origin of damage (5). Moreover, the predictive value of SDF in both natural pregnancy and ART outcomes has been consistently reported from various centers by utilizing different testing methods in a wide range of patients (6). In fact, various SDF tests including sperm chromatin structure assay (SCSA), sperm chromatin dispersion (SCD) and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assays have correlation coefficients Editorial