Clinical use of sperm DNA fragmentation analysis results, a practical example of how to deal with too much information from the literature in reproductive medicine

tau.amegroups.com © Translational Andrology and Urology. All rights reserved. Although a huge amount of information regarding the origin, causes, and impact on reproductive implications of DNA fragmentation in spermatozoa has been raised in the last decades (1), the way to deal with it from the practical and clinical perspective remains unclear. Research on this topic has been favored by the easiness to gather biological samples to be analyzed, the insignificant annoyance or disturbance for the patients, the wide availability and relatively low cost of the tests to measure sperm DNA strand breaks together with the potential interest generated from the pioneering works linking DNA fragmentation in sperm to reproductive results. Paradoxically, this originated, instead of a bulk of evidences leading to straightforward clinical recommendations and behavior, a significant background noise and confusion about when to ask for these tests, how to deal and manage the results, how to inform the patients and what recommendations, either medical treatments for patients or laboratory techniques for sperm selection are needed to be applied in order to improve sperm quality, to (theoretically) enhance reproductive results. Hypothetically speaking, having damaged DNA in sperm could lead to worse reproductive results or mid-long term health problems in offspring, given that this is the way genetic information is delivered to the next generation. Fortunately, the evidence available so far may relax these assertions. First, the ability of the oocyte to repair, at least to some extent, DNA damage (2). This means that samples with low to moderate damage, combined with good quality oocyte may exert no effect on reproductive outcomes. Second, the fact that only a small percentage of sperm DNA encodes biologically relevant data (3), and sperm DNA fragmentation (SDF) tests are still not able to point where the break is located, or if there are expected pathological consequences conditioned by the location of detected breaks. Moreover, using DNA fragmentation as a predictive tool is likely to be a mistake. Probably, no sperm diagnostic tool could ever be developed, since measuring any marker in sperm will hardly predict the results of combining sperm with oocytes and then endometrial receptivity, and also, as it has been previously suggested, sperm quality seems to be multifactorial given the number of molecular factors related with sperm function. Concerning assisted reproductive technology (ART), also there is an existing limitation regarding the fact that any sperm analyzed this way, can’t be used with reproductive purposes. At most, the measurement of a degree of similarity with previously successful samples employed as a model, and ideally, the development of treatments or techniques to improve sperm selection is aimed. This could be useful to establish recommendations about what to do regarding SDF results aiming to provide our patients the best counseling possible and improve their reproductive chances (4). Commentary