Treatments & Options - Fertility Preservation - Resources
In this section, Fertility Preservation Resources, we explain how the fertility preservation field is currently being boosted by the wide acceptance of egg freezing as a fertility preservation option.
History of fertility preservation
For more than 40 years, sperm has been frozen and thawed and used successfully for in vitro fertilization (IVF). And for about 30 years, embryos have been too. But harvesting and freezing oocytes (unfertilized eggs) has been a challenge, until now. Egg freezing was once considered experimental, but it is slowly making its way into the mainstream.
New freezing techniques
A rapid freezing process called vitrification is making it possible for women to harvest their eggs and freeze them, unfertilized, for a variety of reasons. And the advantages of the process are enormous. We explain the process below:
- Currently embryos are frozen by first being exposed to cryoprotectants that dehydrates, or removes water, from the cells.
- Next, the embryos are cooled slowly and then stored in liquid nitrogen. Because individual eggs have increased water content, a zona pellucida and a cytoskeleton, they are easily damaged with the freezing process resulting in lower pregnancy rates.
- Now, vitrification prevents this from happening. The process uses higher concentrations of cryoprotectants and much faster cooling rates than traditional freezing methods.
- Eggs are cooled in tiny straws and freeze at a rate of several thousand degrees per minute.
- This fast freezing helps to prevent the destructive ice crystals from forming in the egg, so the cells are less likely to burst.
- Once vitrified, the egg is stored in liquid nitrogen until it is thawed for fertilization and implantation.
Successful pregnancy with frozen eggs is not guaranteed. However, recent success rates of frozen eggs are promising.
Meet with a reproductive endocrinologist to learn more about your female fertility preservation options. He or she can guide you through the egg freezing process.