Die intrazytoplasmatische injektion von spermatiden bei postmeiotischem reifungsarrest

The microinjection procedure is the established method of choice in treatment of severe male factor subfertility. Recent studies have shown that fertilization and cleavage of oocytes can be achieved even with the injection of immature sperm cells, such as round and elongated spermatids, offering a new treatment possibility for patients with postmeiotic maturation arrest. However, the rate of ongoing pregnancies is still low compared to the pregnancy rates achieved by injection of mature spermatozoa. Especially in the case of round spermatid injection, diverse difficulties arise for the IVF laboratory team, for example the identification and differentiation from other round cells in the sample and the lack of vitality marks. Recently, the use of immature gametes has been thought to lead to higher risks of genetic defects. Therefore the injection of immature sperms should be a method of choice only in cases of total absence of mature spermatids and free spermatozoa.