Donation of oocytes (eggs) is a quite common phenomenon. The need for a donor egg arises when a woman cannot produce the sufficient number of oocysts necessary for in vitro fertilization on her own, even with the help of the most contemporary medical methods. There is another situation, when the quality of cells is not suitable for extra-corporal fertilization .The reasons for such cases can be very diverse. But as practice shows, natural age-related changes are the most common reason. One should take into consideration that every woman has a different eggs reserve, or, using a medical vocabulary, follicular or ovarian reserve, and it can differ significantly.