Within the realm of fertility treatment solutions, researchers are continually searching for the latest scientific and technological discoveries to enhance their procedures. Where experts in oocyte freezing are concerned, a flash-freezing technique known as vitrification is one of the most significant developments of the last century.
The question is, why?
What is it about this innovative technology that has made it such a prominent player in the world of infertility?
From long-term storage capabilities to improved thawing success, cryopreservation not only enhanced the likelihood of having successful fertility treatment but allowed more people than ever before to build something they’d previously only dreamed of having – a family.
How Were Oocytes Frozen Before Vitrification?
In the days before cryopreservation techniques made their way onto the fertility scene, lab workers relied on antiquated slow-freeze technology (also known as controlled-rate freezing) to freeze and store eggs, sperm, and developing embryos.
This procedure entailed slowly cooling collected eggs and other specimens until they eventually reached -320° Fahrenheit. The samples were held inside a controlled-rate freezer that lab workers filled with liquid nitrogen to assist with cooling during the process.
However, the problem with this technique was that the longer it took to complete the freezing process, the higher the chance there was of ice crystal formation developing inside the oocytes. Once ice crystals were present, they would cause significant damage to the overall structure of cells.
Regretfully, there was only a 66% thawing survival rate for eggs that were frozen and stored using this method.
Why is Vitrification the Better Freezing Option for a Woman’s Eggs?
In comparing vitrification with controlled-rate freezing, the results indicate vitrified eggs have a better chance of surviving storage and thawing.
Before freezing takes place, eggs are exposed to an advanced collection of cryoprotectants. These substances help ensure the oocytes maintain the same quality they have upon collection. Cryoprotectants also significantly decrease the risk of ice crystal formation and cell structure damage.
After exposure to these cryoprotectants, the eggs are placed into liquid nitrogen for flash-freezing and remain there until they’re ready to be used.
Remarkably, one peer-reviewed study reported that vitrified eggs have a 90 – 97% chance of surviving the thawing process.
However, it’s worth noting that if someone’s planning on thawing and fertilizing previously frozen eggs during an IVF cycle, they’ll need to be fertilized using intracytoplasmic sperm injection (ICSI).
What Are Some Benefits of Using Cryopreservation Techniques?
Thanks to the high success rates seen with vitrification, it opens the doors to more versatility when it comes to oocyte freezing.
Some of the most common reasons people choose to freeze their eggs include:
- Future IVF Cycles: When someone undergoes egg retrieval during an IVF cycle, doctors can sometimes retrieve more eggs than necessary for a single transfer. In these cases, facilities can store the remaining eggs for future use.
- Egg Donation: Given the high success rates with vitrified eggs, more people are turning to frozen donor eggs than ever before. Furthermore, if someone is interested in donating their eggs to a family in need, they now have frozen egg donation available to them rather than undergoing a fresh donor egg cycle.
- Waiting to Start a Family: Studies show people are waiting longer to start a family than they did in decades past. In fact, the average age of first-time parents is now 29.9 years old. Since egg quality and fertility begin to decline around the age of thirty, some people are starting to rely on oocyte freezing to protect their future fertility until they’re ready to have a baby.
- Preventative Measures Before Chemo or Radiation: Research shows that cancer treatments, such as chemotherapy and radiation, can negatively impact the quality of eggs (oocytes). Some people elect to collect and store their eggs for future use before treatment begins to avoid these issues.
- Genetic Testing: Future parents can now have their eggs tested for genetic diseases and conditions before freezing takes place.
Taking Control of Fertility with Cryogenic Oocyte Freezing
There are many reasons why someone might be interested in storing their eggs for future use. Maybe it’s not the right time to start a family, or perhaps they’re interested in providing frozen donor eggs so another person or couple may start their own family. Either way, vitrification has opened up the realm of possibilities for our fertility and family planning processes.
There’s no longer an urgency to have a baby when you’re not ready or incapable of doing so. You can now put pregnancy on hold and find comfort in the thought that your eggs – or someone else’s – are safely stored and protected by this innovative technology.
