Egg Freezing – What to Expect

The technology of egg freezing is a boon for women today who wish to delay childbearing, due to medical needs or changing priorities or for any other reasons. After IVF, egg freezing is the next biggest technological advancement in the field of fertility medicine. The change from frozen embryos to frozen eggs has now given single women an opportunity to delay motherhood. By freezing their eggs, women can control their fertility and get pregnant at a time of their choosing.

This Assisted Reproductive Technology is primarily used as a means to extend fertility by preserving Oocytes for later use (e.g. a woman can get pregnant at 40 using the eggs she had frozen at 30) or to protect fertility when other medical conditions or treatments may affect it adversely (e.g. before chemotherapy or early menopause). The process involves hormonal simulation akin to IVF before retrieving the eggs through a short invasive procedure under sedation.

Depending on the patient’s age, the required number of eggs are harvested in one or more cycles and then frozen in the laboratory through a process called vitrification. Eggs frozen in this way can be retained for up to 10 years or more without any loss in the quality of the eggs. When the patient is ready for pregnancy, these frozen eggs are thawed and impregnated with sperm and the embryo is placed in the uterus, similar to IVF. About 2000 babies have been born in this way since 1986, and although more data is scarce to come by, the statistics so far imply that egg freezing has fairly satisfactory outcomes.

What Is Egg Freezing?

Egg freezing or egg banking or oocyte cryopreservation (as it is called by doctors) is a new technique in Assisted Reproductive Technology (ART) whereby the eggs of a woman of childbearing age are frozen and stored for later use. This is a method to preserve and control the fertility of a woman who for various reasons, may choose to have children at a later period of time.

Is Egg Freezing Safe?

The first baby to be conceived from a frozen egg was born in 1986 and ever since two thousand more babies have come into the world in this way. No apparent increase in the rate of birth defects has been noticed so far (as compared to the general statistics) in babies conceived from frozen eggs. Risks in the process of harvesting eggs for egg freezing are comparable to those from other IVF procedures such as Ovarian stimulation, e.g. infection, bleeding, etc.

When Should You Freeze Your Eggs?

The best age to freeze your eggs is in the late twenties and early thirties when you are living your healthiest and most fertile years because the fertility (quality) and number (quantity) of eggs harvested decides the success rate of conceiving later. Also, this is usually the age when a woman decides if she wants to delay parenthood and considers options such as egg freezing.

Why Do Women Freeze Their Eggs?

Women may choose to freeze their eggs for a variety of reasons, both medical and social. Primarily, women with conditions requiring fertility-impairing medical treatment opt for egg freezing, in order to preserve their chances of bearing children later on. For example, women undergoing cancer treatment (radiation or chemotherapy), those with an ovarian disease or undergoing surgery that might affect the ovaries or with a family history of early menopause, can freeze their eggs before starting with the treatment. Nowadays, even healthy women who wish to delay having children for career or relationship reasons are electing to freeze their eggs.

What If Your Age Is Above 38?

Most doctors would agree that the best age to freeze eggs is below 38. In fact, many centres have a cutoff age of 38-40 for freezing eggs. This is because eggs harvested from women under 38 are more fertile and have greater chances of a successful outcome after thawing. Also, the number of eggs can be expected to be harvested before age 38 than in the forties. Once a woman crosses 40, the chances of harvesting enough good quality eggs for egg freezing as well as the chances of getting pregnant are reduced.

How Many Eggs Should be Stored for Achieving Pregnancy?

A woman below 38 normally produces 10-20 eggs per menstrual cycle. The vitrification or thawing rates and egg fertilisation rates vary between 75-80%, i.e. out of 10 frozen eggs, 7-8 can be thawed, and about 5-6 can be fertilised. Not all fertilised embryos can be implanted, however. Hence, it is recommended to store at least 8-10 eggs for each planned attempt at pregnancy. And, it is better to freeze more eggs with increasing age to increase the chances of pregnancy, while also weighing other factors, such as the cost.

How Long Can You Freeze the Eggs?

Eggs are frozen at temperatures of -190 degrees Celsius in liquid Nitrogen, just as frozen embryos are. It is assumed that storing eggs for longer periods does not affect the quality of the eggs. However, there is no hard evidence on this, as frozen eggs have so far only been stored for a period of up to 4-5 years. Even though theoretically, eggs can be frozen indefinitely and retrieved late, doctors recommend that frozen eggs be used before the woman reaches 45 years of age in order to achieve a successful pregnancy outcome.

How to Prepare to Freeze the Eggs?

Egg freezing is a major decision and must be well-thought over. So, it is necessary to first confer with a fertility specialist whether egg freezing is suitable or necessary, based on medical history, age and future plans about having children. Once it has been decided to go in for egg freezing, the doctor will monitor the patient’s fertility and hormone levels as well as follicular growth through ultrasounds and blood tests, as frequently as every two days. These are necessary to ensure that a good number of mature eggs are harvested during the procedure. For the same reason, it is also advisable to follow a healthy lifestyle prior to egg freezing.

Process of Freezing Eggs

The process of freezing eggs typically has three phases – ovarian stimulation, follicular monitoring (and bloodwork) and egg retrieval. The first two phases are similar to IVF, wherein the patient is given hormone injections for 7-10 days to stimulate the ovaries to produce eggs and speed up their ripening. During this period, the follicles are monitored through frequent ultrasounds and blood tests. A day prior to the harvesting, the patient is administered a medication that triggers ovulation. The mature eggs are then harvested through a minimally invasive procedure under anaesthesia, which takes less than half an hour. The eggs so retrieved are frozen immediately.

What Happens After the Procedure?

Once the eggs are harvested, they are frozen (cryopreserved or vitrified) for later use. The process of retrieving eggs may have certain side effects such as bloating, infection or bleeding or other side effects related to Ovarian hyperstimulation syndrome. However, most women return to their normal schedule by the next day after the procedure.

How Does Egg Freezing Work?

Egg freezing involves harvesting mature eggs from a woman after hormonal treatment similar to IVF. Once enough healthy eggs are retrieved, they are frozen through a flash-freezing method called vitrification, in which the eggs are frozen in liquid Nitrogen rapidly at temperatures of -190 degrees Celsius. These cryopreserved eggs are thawed when required and combined with sperm cells, and the resulting embryo is implanted into the patient.

Success Rate of Oocyte Cryopreservation

The success rate of developing viable pregnancies from frozen eggs depends on a variety of factors, including the number and quality of eggs harvested, the age of the woman when the eggs were harvested as well as the age of the woman at the time of pregnancy, the freezing technology used, etc. In general, a good number of healthy eggs harvested from a younger woman (between 25-35) have a better chance of leading to a pregnancy. However, there is not enough data available yet to confirm the success rates.

Cost of Egg Freezing In India

As it is a new technology in fertility medicine, egg freezing involves considerable costs. It basically includes two types of costs. The cost of the procedure for retrieval of eggs and freezing them is similar to an IVF procedure and may vary between Rs.50,000 to Rs.1 lakh. Once the eggs are frozen, the cost of retaining them in the frozen state is a recurring annual cost and may be anywhere between Rs.15,000 to Rs.30,000 per year.

What Are the Potential Risks of Egg Freezing?

In egg freezing, the ovaries of the woman are stimulated through drugs to produce more eggs. This may sometimes lead to ovarian hyperstimulation syndrome, where the ovaries become swollen and painful. This causes other symptoms like vomiting, bloating and sometimes even fatal symptoms like blood clots.

The medical procedure for retrieving the eggs itself carries risks such as bleeding or risks from anaesthesia.

To be able to retrieve enough eggs for freezing, a woman may have to undergo multiple cycles of egg freezing, as a result of which the risks may be multiplied.

At present, data is lacking about the risks of pregnancy from frozen eggs and other social risks.

Few Facts About Egg Freezing

• 25 to 35 is the best age to freeze your eggs.
• Pregnancy is not guaranteed with frozen eggs.
• Most frozen eggs are not used.
• Same hormone injections are used in this process as in IVF.
• Egg freezing is currently an expensive affair.

Egg freezing is a new-age reproductive technology that allows women to freeze their eggs and use them later to conceive, thus effectively delaying motherhood. Like many other reproductive technologies, egg freezing also has its advantages and disadvantages and is not yet fully understood in all its implications. Any decision on freezing your eggs is best made with the help of a qualified fertility specialist, after taking into consideration the costs, risks and benefits.

Also Read: In Vitro Fertilisation (IVF) for Infertility Treatment