Sperm DNA damage and assisted reproductive technologies: reasons to be cautious!

Is there a more important situation where one should apply the precautionary principle than in assisted reproductive technologies (ART)? Although ART are formidable answers to the distress of couples having difficulties to conceive, these technologies are far from being totally well controlled. The worldwide increasing demand on ART is by itself an alarming situation that should promote more research on the multifactorial origins of decreasing human fertility. However, the clinical success of ART (although perfectible!) has essentially produced an opposite effect with a slowdown in the effort and money dedicated to the understanding of human infertility. Why bother to understand what is going wrong when one can bypass most of the blockages observed either structural or functional? While a lot of energy and money have been spent to improve ART success rate, the improvement obtained is not up to our expectations and ART success rate has remained at a mere 25 % overall for the past 30 years. This situation is worth analyzing since it could reveal that either we are looking in the wrong directions to improve ART or that the processes of ART generates stresses which annihilate the expected improvements. At the same time, progress made in basic sciences indicates possible reasons for caution that should be seriously considered by clinicians and geneticists.