Naturally, a woman produces one mature egg each month. If this egg is fertilized, it will become an embryo and the woman will become pregnant. However, if it is not fertilized, it will be eliminated during menstruation.
A healthy woman has around 400,000 oocytes, at birth, in her ovaries. These oocytes are the immature future eggs. During the fertile period of her life, only one of every thousand (no more than 400) will reach maturity and therefore have the possibility of being fertilized.
Each month, several oocytes start, at the same time, the development process which ends on the day of ovulation. Only one of them will have reached maturity at this time whilst the rest will atrophy and become useless. In this way, the womanís body prepares for pregnancy, if that is her wish. If not, this egg becomes unnecessary and is eliminated during the menstruation.
Egg donation is defined as the surrendering (anonymously, freely and altruistically) of some of the eggs of one woman so that another can have a child. These eggs come, therefore, from the natural reserve present in the ovaries, and which, usually are never used. Therefore, egg donation, although it consists of surrendering part of oneís self to another person, does not really involve the definitive loss of something irreplaceable. It could be described as a way of making use of some of the eggs that a woman would never be able to use. You give away something you will never use, you do not lose anything.