Oocyte Vitrification is one of the techniques used in preserving a woman’s fertility therefore allowing reproductive capacity to be postponed until the time is right. With the vitrification process, preserved oocytes have the same viability as they did at the time of freezing.
Vitrification of oocytes is a solidification process in which the oocytes are treated with cryoprotective substances and submerged in liquid nitrogen. (ASRM) The steps to prepare the patient’s body for retrieval are the same as a fresh cycle retrieval. First, we stimulate the female’s ovaries with hormones to aid in follicle production. Then, instead of fertilizing these eggs, they are vitrified and subsequently stored in liquid nitrogen.
Vitrification V. Slow-Freezing:
Recent studies suggest that vitrification is superior to and presents less risk to the embryo than the older “slow-freeze” method.
Slow Freezing is the preservation process in which an egg is cooled very slowly, until it reaches the final storing temperature of -320º Fahrenheit. At this temperature all biological processes cease inside the cell, therefor allowing the egg to be safely preserved. In total, the entire process takes approximately two to three hours.
In contrast, vitrification is a “flash freezing” method that cools cells so rapidly to -320 ºF that they become “glass-like” or “vitrified.” While the slow freezing technique takes hours, vitrification is finished in just minutes.
This is important to the success of egg freezing because the longer the freezing process takes, the higher the chances that ice crystals will form inside the cell. The speed of vitrification allows for a higher concentration of cryoprotectants that decreases the risk of destructive ice crystals. Typically 97% of vitrified oocytes survive the process.
Oocyte Vitrification Is Recommended For:
- Patients about to undergo treatment for cancer or another illness that may affect future fertility potential.Certain medical treatments such as radiation or chemotherapy can harm fertility. Vitrification allows these patients to conceive a biological child post-treatment.
- Frozen Embryo Transfer with IVF.Frozen transfers are utilized for several reasons. For instance, some patients are unable to complete a fresh cycle due to an increased risk of hyper stimulation.
- Preserving younger eggs now for future use. Since pregnancy rates are largely effected by the age of the female’s eggs, freezing them at a younger age may help preserve a woman’s ability to reproduce at a more desirable time
Oocyte vitrification is recommended in numerous and very wide-ranging situations, but the common denominator is postponing fertilization of the oocytes and/or pregnancy. Our team at Brown Fertility is dedicated to educating our patients on all aspects of the fertility preservation process and will guide them in deciding which option fits their specific needs.