Social Egg Freezing

Egg freezing is the process of extracting, freezing and storing a woman’s eggs so that they may be used to conceive a child at a later date. There are no absolute guarantees but egg freezing does give a woman the opportunity to try for a baby in the future.

There are three general steps involved in an egg freezing cycle.

1. Stimulation of the ovaries to encourage development and maturation of the eggs:

Under the care of a consultant gynaecologist, the woman is given fertility medications to stimulate her ovaries to produce many follicles.

Follicles are the small fluid-filled structures which develop on the ovaries, each of which will hopefully contain an egg.

The number and size of the developing follicles is measured by trans-vaginal ultrasound scans. The exact number of follicles which develop varies between patients, but the average is about 10. The final preparation for egg retrieval involves a hormone injection which mimics the natural trigger for ovulation. Egg retrieval will take place 36-38 hours after this injection.

2. Retrieval of the eggs:

Egg retrieval is a minor theatre procedure which is carried out on an outpatient basis under local anaesthesia. The trans-vaginal ultrasound probe is used to visualise the ovaries and a needle attached to the probe is passed through the vaginal wall into the follicles.

The fluid within each follicle is aspirated and then examined in the IVF laboratory for the presence of an egg. After identification, the eggs are washed and transferred to petri dishes in an incubator.

3. Freezing of the eggs:

The eggs are frozen in the laboratory using a method known as vitrification. The eggs can then be stored until the woman is ready to use them, when they can be thawed and used for IVF.

Egg freezing is a relatively new procedure, because of the complications involved in preserving eggs. The fact that the egg is the largest cell in the body and high in water content makes it difficult to freeze safely. Traditional cryopreservation technology caused crystals which resulted in damage to a high proportion of eggs, making freezing unviable.

Vitrification is a new cryopreservation technology. It is a flash-freezing process where unfertilised eggs are placed in a special freezing solution, which helps eggs to survive freezing and thawing so that they are intact and viable.

Current pregnancy rates following the use of thawed, vitrified eggs have begun to rival those achieved when fresh, unfrozen eggs are used. Thousands of babies have been born worldwide to those who have recovered from cancer and other serious illness, following egg vitrification.

The World Health Organisation (WHO) states that one in six people experience fertility challenges. The reason for this is that female fertility reaches a peak in the early 20s and begins to decline significantly from age 30 onwards.

• Women are most fertile between the ages of 20 and 24
• At 35, you’re half as fertile as you were at 25
• At 40, you’re half as fertile as you were at 35

A woman’s ovaries age in the same way that normal aging affects all of her organs and tissues. Most women have about 300,000 eggs in their ovaries at puberty. For each egg that matures and is released during the menstrual cycle, at least 500 eggs do not mature and are absorbed by the body.

As a woman ages, the remaining eggs in her ovaries also age, making them less capable of fertilisation and their embryos less capable of implanting.

Fertilisation is also associated with a higher risk of genetic abnormalities such as chromosomal abnormalities. The risk of a chromosomal abnormality in a woman aged 20 years is one in 500 while the risk in a woman age 45 is one in 20.

Where a woman decides to freeze her eggs for non-medical reasons, we advise that she be under the age of 35 at the time of egg freezing.

In specific circumstances, if you have a partner you may choose to freeze embryos for future fertility treatment. This involves undergoing an IVF cycle to retrieve the eggs which are then fertilised in the laboratory and the resulting embryos are stored.

It's important to note that where embryos are created, both partners have the right to withdraw their consent for future use of the embryos. The serious consequences of this should be considered as it could result in you losing access to your own reproductive material. As a woman, freezing your eggs, gives you more autonomy over your pregnancy options in the future.