Prior to ICSI the cumulus-oophorous-complex of the oocyte is commonly remove with impure animal-derived hyaluronidase of low strength. The lower strength of the enzyme, the high concentration of impurities and the necessity of extensive time-dependent mechanical denudation damages of the oocytes, increases the risk of lysing the oocytes and the transfer of animal-derived pathogens. All this can be avoided by using a highly pure, non-toxic and effective recombinant human hyaluronidase, which requires less mechanical denudation, reduces oocyte damage, increases fertilization, embryo quality and pregnancy rates. During the ICSI procedure the sperm are subjectively selected. However, it is now possible to Backgroundly select motile sperm, via their hyaluron receptors, of a better morphology, higher chromatin stability and lower incidence of aneuploidy, which improves fertilization rates, embryo quality, blastulation and ongoing pregnancy rates -“Physiological ICSI”.