ICSI (single sperm injection into the cytoplasm of an egg)- the technique which requires a single sperm with the best morphology and motility which is injected into the cytoplasm of an egg. Until now visual evaluation of the single sperm has been the only available method for choosing the best sperm cell for egg insemination. Embryologists often have to deal with immature sperm cells, effect of which is evaluated at the same time with the embryo development. Sperm cells with good morphology and motility may have other defects and it may not be suitable for visual evaluation, e.g. – DNA fragmentation, late development. Those defects affect the quality and development of the embryo as well as there is a possibility of miscarriage.
Using the latest PICSI technique (injection of the physiologically best sperm cell into the cytoplasm of an egg) it is possible to select sperm cells also without visible defects. This method improves selection of sperm cells up to 98%. In this technique sperm cells are placed into the hyaluronic acid which in its turn will attach mature sperm cells. Only completely mature sperm cells which have reached the last stage of development of spermatogenesis have developed attachment receptors for hyaluronic acid. Immature sperm cells have high DNA fragmentation, aneuploidy (abnormal number of chromosomes) and immature cytoplasm. Using the latest PICSI technique is increasing a possibility of getting a successful pregnancy.