Egg Freezing (Cryopreservation)

What is Egg Freezing?

Egg freezing, or mature oocyte cryopreservation, utilizes advanced technology to freeze and store unfertilized eggs.

While the first live birth from a frozen egg was reported in 1986, it was not until late 2012 that the American Society for Reproductive Medicine (ASRM) announced egg freezing was not an experimental process.

Sperm freezing has been in wide use for many years. But due to the large size and water content of the human oocyte (egg), cryopreservation has been a difficult process, as ice crystals form that can damage the egg. Technological advancements in the freezing/thawing process, and in IVF, have increased the chances of success with frozen eggs.

Who Can Benefit From Freezing Eggs?

Egg freezing is an option for many individuals for various reasons.

• Cancer treatment. Chemotherapy, radiation, or surgical treatments for certain types of cancer can result in infertility. Freezing eggs before beginning treatment gives you the option to use healthy eggs to conceive after recovering from cancer. This is also known as oncofertility preservation.
• Career-focused. Some individuals may wish to delay pregnancy to focus on their careers. Egg freezing offers an opportunity to preserve the eggs at their healthiest, which is when an individual is at a younger age, to then be used later.
• Relationship reasons. People may want to delay pregnancy until they find the right partner, but want to preserve their eggs when they are younger.
• Donated eggs. LGBTQ+ couples or those using donated eggs to have a child often use frozen eggs.
• Transgender and transitioning. Egg freezing is an option for individuals who are transitioning and would like to preserve their eggs for future use.
• Job hazards. For those who work with hazardous chemicals, egg freezing beforehand can store healthy oocytes before they can be damaged.
• Ethical or religious concerns. Some individuals undergoing IVF may not want to create more embryos than can be used for pregnancy. In order to avoid this, eggs can be retrieved and frozen, then utilized singly in the future to create one embryo.

What is the Egg Freezing Process?

The patient will take an ovulation-inducing medication for 10 to 12 days in order to stimulate the ovaries to produce multiple eggs for retrieval.

During this time, we monitor blood levels as well as perform ultrasound monitoring to ensure the appropriate response to the medication is occurring. The mature eggs are then retrieved, with the woman or transgender man under mild anesthesia. This is an outpatient procedure, which usually lasts 30 minutes.

Eggs are then flash-frozen through a process known as vitrification. The eggs are bathed in a cryoprotectant and rapidly cooled to -320 degrees Fahrenheit in liquid nitrogen. This process suspends biological activity until the eggs are thawed.

When the individual is ready to begin the next part of fertility treatment, the frozen egg(s) are thawed by an embryologist and, typically, fertilized through an IVF technique known as intracytoplasmic sperm injection (ICSI). This process optimizes the chances of fertilization as it injects a single sperm directly into the cytoplasm of the egg where fertilization occurs.

The fertilized egg, or embryo, is then transferred into the patient’s uterus.

How Can a Patient Prepare for Egg Freezing?

Before beginning mature oocyte cryopreservation, a fertility specialist may recommend testing the ovarian reserve, which never increases but continually decreases. This test can help determine the quality and quantity of eggs. The results of this test can help the physician understand how the person may respond to the medication.

Screening for any infectious diseases, such as hepatitis B or C and HIV, may also be performed.

How Much Does Egg Freezing Cost?

Egg freezing cost can be broken down into three categories:

• Consultation, hormonal medication, and egg retrieval
• Storage
• Transfer

As each person and situation is unique, the cost may vary. But typically the total cost can be around $20,000. Freezing eggs is approximately $10,000-$12,000, with an annual storage fee that is typically about $500.

What are the Risks of Egg Freezing?

The main risk with egg freezing is the loss of eggs in the vitrification and thawing processes.

According to a study published by ASRM, the survival rate of oocytes after freezing and warming ranged between 90-97 percent.

Meet our lab team

In order to retrieve more than the normal one egg per cycle the ovaries release, medication is used to increase egg production. This can result in another risk associated with the process called ovarian hyperstimulation syndrome (OHSS), a rare complication of ovarian stimulation medication.

In mild or moderate OHSS cases, symptoms can include breast tenderness, headaches, nausea, irritability, or fatigue. In severe cases, blood clots, abdominal pain, vomiting, and shortness of breath may occur. According to the National Institutes of Health, less than 0.1 to 2 percent of patients experience this form of OHSS.

Is Using Frozen Eggs Less Successful than Using a Fresh Egg Transfer?

Of the 90-97 percent of frozen eggs that survive the thawing process, successful fertilization occurs in roughly 75 percent. The clinical pregnancy rates per transfer range from 36-61 percent.

According to ASRM, the fertilization and pregnancy rates of using frozen eggs compared to IVF using ICSI and fresh eggs are similar.

How Long Can Eggs Be Frozen?

There is limited information on the impact of long-term cryopreservation on the chances of success. According to ASRM, there appears to be no difference between eggs frozen and thawed up to 48 months compared to earlier thaws.