The techniques of assisted reproduction have made it possible for a woman, whose eggs are not of the quality necessary to achieve a pregnancy by themselves, access maternity thanks to the altruism of another woman, with higher quality eggs.
Before accessing a donation program, the prospective donor must undergo an important selection process that assesses her ability to be a donor, in which both physical and psychological status are studied before allowing her to donate eggs.
The IVF process with an egg donor can be done in two very different ways depending on the origin of the ovules, but the first part of the process is the same for both types.
Ovarian stimulation
The donor is stimulated just as a patient who is going to undergo IVF would. The gynecologist stops the behavior of her ovaries and hormones are applied so that there is a high production of ovules in that cycle. Serial ultrasounds are performed and as soon as the follicles are large enough, ovulation is triggered and the ovules are removed in the laboratory.
Fresh donation
The donor and the recipient have to be coordinated. The donor is stimulated while the recipient is preparing her endometrium. In the same cycle, the eggs are extracted from the donor, then fertilized in the laboratory with semen from the partner of the recipient, and if the embryos develop well and are of good quality, they will be transferred to the patient's uterus, for its implementation. In the case that there are excess quality embryos, they can be frozen, being owned by the couple of patients. The advantage of fresh donation is that the times are similar to an IVF of the couple: stimulation and transfer in 15 days. The disadvantage of this technique is that if the donor does not respond well to ovarian stimulation, a cycle may be lost.
Donation of vitrified oocytes
The donor is stimulated with hormones but does not have an assigned recipient that is preparing her endometrium at the same time. The oocytes are extracted in the operating room, and after evaluating the maturity, the mature ones are vitrified, frozen in an ultrafast manner. They are kept in liquid nitrogen until a patient that requires an egg donation is compatible with the physical characteristics of the donor.
At this time, the endometrium of the recipient patient is prepared, the oocytes are devitrified and inseminated with semen from the partner of the recipient. Fertilization and embryonic development are observed in the laboratory and after 3 or 5 days from insemination, they are transferred to the prepared uterus of the recipient so that they implant and give rise to a pregnancy, which will be confirmed 15 days later with an analysis of the pregnancy hormone, beta HCG.