 The spermatozoa will be prepared in the standard fashion and utilized for injection after exposure to a membrane permeabilizing agent. The injected oocytes will be then exposed to the previously mentioned activating agents for the purpose of inducing embryo development. The successfully fertilized oocytes will be further kept in culture for up to 5 days as per standard IVFICSI. Results in terms of fertilization and embryo cleavage will be assessed and monitored for the remainder of the culture period. Developing embryos selected according to standard criteria will be replaced to the patient or will be cryopreserved. 