For many decades cryopreservation of sperm and embryos has been performed successfully using the slow-freeze method. In the traditional slow-freeze method, the cell to be frozen is immersed in a special solution (cryoprotectant) that withdraws the water from the cell over many hours to minimize the formation of ice crystals that can expand during thawing and destroys the mechanism that aligns the chromosomes. Unfortunately, due to the large size of the egg and its high water content, achieving a state of complete dehydration for egg freezing was very difficult. Although the first live birth from frozen eggs occurred in 1986, until recently, egg survival rates of 20% and pregnancy rates of 10% were too low to make egg cryopreservation practical.
In 2008 a new ultra-rapid freezing technology called vitrification was introduced to freeze human embryos. By taking cells from room temperature to -196 degrees C in a fraction of a second, vitrification completely avoids the formation of ice crystals. The results are higher rates of embryo survival and live births seen with frozen embryo transfer cycles.
The same vitrification process to freeze embryos was slightly modified to allow successful freezing of eggs. Preliminary studies have shown that the ultra-rapid freezing process completely avoids the formation of ice crystals to allow achievement of an egg survival rate of 90% and pregnancy rates of 50% or higher in certain groups of patients. As of October 2012, the American Society of Reproductive Medicine has removed the “experimental” label and endorsed oocyte vitrification for medical indications.
The Egg Freezing Cycle- from Start to Finish
The entire process takes about 4-6 weeks from start to finish and is consisted of the following steps:
1. Evaluation of your egg reserve:
Assessing your ovarian reserve is important. A baseline ultrasound during the first three days of your menses allows us to count the number of eggs available per cycle. A blood level of AMH measures your long term reserve. An antral follicle count of 10 or higher and an AMH level of 1.5 ng/ml or higher suggest normal egg reserve.
2. Prestimulation cycle:
If you have a normal egg reserve, you might be put on birth control pills (BCP) for two weeks to rest the ovaries. However, if your egg reserve is low, you will not use BCP.
3. Ovarian stimulation cycle:
The stimulation protocol depends on how many eggs your ovaries can produce in a cycle and how many children you desire in the future. For about 10-12 days, you will use injectable medications to stimulate your ovaries while undergoing close monitoring with sonograms and hormone levels obtained by blood draws.
4. Egg retrieval:
You will undergo deep IV anesthesia for about 20 minutes while eggs are aspirated from both ovaries using a thin needle on top of a vaginal ultrasound probe. You will not feel or remember anything during the retrieval procedure and will wake up instantly afterward. Mild cramping or discomfort may occur and can be treated by medications as needed. You will rest for about 30 minutes in a recovery room before being discharged. Due to the effects of anesthesia, you will need to have someone available to drive you home after the procedure. You should be able to return to regular activity later that day. Over the next few days, you may feel mild abdominal discomfort and bloating sensations but these will likely resolve within 1-2 weeks.
5. Egg freezing and storage:
The eggs will first be stripped of the attached cells and assessed for maturity. Only mature eggs will be frozen. Immature eggs are incubated in special media and observed for signs of maturity for later freezing.
Mature eggs are immersed in a cryoprotectant solution to remove water from the egg cells (dehydration).
The ‘dehydrated’ eggs are put into specialized straws and flash frozen in milliseconds. The frozen straws are finally stored in a liquid nitrogen tank.
How Many Eggs Should I Freeze?
We recommend that you freeze about 8-10 eggs for every pregnancy you plan to have. Assuming a 90% egg survival rate, thawing of 10 eggs would result in 9 viable eggs. With an average fertilization rate with ICSI of 70%, about 5-6 eggs would fertilize to eventually provide 2 blastocysts after day 5 of culture.
A large study published in 2016 from a prominent IVF program provided useful data on how many eggs a woman needs to freeze to have a certain number of children. The graphs below reflect some of the data from the study:
What Are the Costs to Freeze Eggs and to Use Them Later?
At IVFMD, the global cost for the egg freezing cycle is $5,500. The global fee takes effect at the start of the stimulation cycle. It covers professional management, facility fee, monitoring sonograms, hormone monitoring, egg retrieval, cryopreservation, and the first year of storage.
Cryostorage for the first year is included in the global fee for egg freezing. Afterward, your eggs will be stored at Repromedics, which is a nationwide center for long-term cryostorage. Its annual storage fee is $500.
The global fee for the egg thawing cycle is $5,000. The global fee takes effect at the start of the hormone replacement cycle. It covers professional management, facility fee, monitoring sonograms, hormone monitoring, egg thawing, ICSI, embryo culture, laser hatching, embryo transfer, and 2 pregnancy tests.
How Do I Use My Frozen Eggs?
When you are ready to use your frozen eggs you will likely go through these steps:
1. Preparation of the uterus
The goal is to prepare the endometrium for the embryos. Estrogen is used for about 2 weeks to grow the endometrium before progesterone is added to mature the uterine lining for implantation.
2. Egg thaw and fertilization
Eggs are thawed and injected with sperm (ICSI) to optimize fertilization since the freezing process can harden the zona (shell) of the egg. A fertilization check is performed the next day (day 1). Normally fertilized eggs are cultured further.
3. Embryo culture
The embryos are allowed to grow in the incubator for at least 5 days in special media and carefully controlled conditions.
4. Embryo transfer
Embryo transfer is conducted on day 5 at the blastocyst stage. Laser hatching of the zona may also be performed to facilitate implantation. A pregnancy test can be performed 10 days later.
If embryo testing is desired, the embryos are biopsied then refrozen until the results are available.
How Successful Is Egg Freezing?
The success in producing a baby from egg freezing depends on the age of the woman at the time her eggs are frozen. The risk of producing abnormal eggs increases significantly after age 35.
Studies have revealed an egg survival rate of 80-90% after being thawed and a fertilization rate of 70-80%, which is about the same as in fresh eggs.
Vitrification experience in Italy (182 couples) had shown similar survival rates after thawing among women of different age groups. Clinical pregnancy rates were lower in women older than age 38. Pregnancy rates per transfer were 49% (age ≤ 34), 24% (age 35-37), 23% (age 38-40), and 22% (age 41-43%).
How safe is egg freezing?
Since 1986 there have been more than 2,000 live births from frozen eggs worldwide. Studies on the safety of egg cryopreservation have revealed the following: There was no difference in chromosomal abnormalities in embryos from frozen eggs compared to those created from fresh eggs. Overall, of the babies born from frozen eggs, only 1.3% birth defects, a rate not significantly different from that seen in naturally conceived infants.
How long should the eggs be stored?
There is limited data on long term storage of eggs. However, one study showed no difference in egg survival rate, embryo quality, pregnancy rate or live birth rate in eggs frozen up to 4 years compared to earlier thaws.
Why do women freeze their eggs?
Women freeze their eggs before proceeding with treatments that can lower their egg reserve or egg quality such as chemotherapy or pelvic radiation for cancers. Many women also want to delay childbearing for personal reasons and freezing their eggs enables them to preserve their reproductive potential. In addition, egg freezing avoids the ethical dilemma of discarding extra embryos. Instead of fertilizing all available eggs in an IVF cycle, some eggs can be frozen for future use. If the first treatment attempt is unsuccessful the frozen eggs can be thawed and fertilized to give the patient another chance to conceive.
Is there a money back guarantee program?
No. However, for patients who fail to conceive 1 year after tubal reversal surgery, we do provide a significant discount for IVF.
Is financing available?
Yes, we work with several programs that can provide you loans to help pay for the surgery.