Frozen (vitrified) donor eggs
At first, donor-women had to be found who were willing to participate in the program for a particular patient, she had to be stimulated to obtain the embryos for this patient. Attempts at freezing egg cells did not give good results.
But it has vastly improved over the past few years due to the fine-tuning of the freezing and thawing protocols. The survival rate of the egg cells after thawing and the viability is a lot better than it was in the past. These improvements can now allow a good pregnancy and a live birth success rates when using frozen egg cells of the donors.
Recently there has been a rapid increase in the banks of donor egg cells, as it allows to provide patients with a large selection of donors, collect biomaterial of those donors whose egg cells are kryo tolerant and invest money in complex genetic research of such donors.
Of course, the use of vitrified egg cells is much more convenient for the fact that it enables to avoid synchronizing cycles of the donor and the recipient, and dependance on the personal circumstances of the donor ,which sometimes can lead to the failure of the program.
The success of the program using frozen donor egg depends on several factors:
- The quality of the egg donor
- The ability of the clinic to perform efficient freezing and thawing procedure of the egg cells, which means, the level of training of the embryologists in the clinic.
In our clinic, we avoid the difference between fresh and frozen oocytes by offering to use in IVF programs a fixed number of oocytes after thawing. In other words, if a part of the egg cells hasn’t thawed, we continue to defrost until their number corresponds to the declared. Currently, we see pregnancy rates in programs with fresh and vitrified oocytes are approximately equal.
We believe that our ability to control all aspects of egg cell freezing process gives us the advantage overthe programs that use fresh donor egg cells. We choose which egg to vitrify and we maintain excellent quality control at freezing and thawing all the egg cells in our laboratory.
Also, the cost advantages of the program with frozen oocytes make them more accessible and convenient for our patients.