What is egg freezing?
Egg freezing is a method of storing a woman’s unfertilised eggs to allow her to try to conceive at a later date, when natural conception would be unlikely. It may be seen as a way of preserving the possibility of fertility for women who are not in a position to become pregnant straight away, or whose fertility is at risk for medical reasons such as cancer treatment.
Frozen eggs may be stored for many years without significant deterioration. When the woman is ready to use her eggs, they are warmed, and then fertilised with sperm. The aim is for the fertilised egg to develop into an embryo, which can then be transferred to the woman’s uterus giving a chance of pregnancy.
- What is the egg freezing process?
To obtain eggs for freezing, a woman will usually have hormonal stimulation for 10 – 12 days, enabling a number of eggs (usually 6 – 15) to mature. There are a variety of stimulation techniques, and you will decide which is best for you in discussion with your fertility specialist.
The stimulation medications are self-administered by a daily injection using a pen device with a small needle. Patients are taught how to do this in an instructive introductory consultation. The injections make the woman feel a little bloated but there are no frequent significant side effects and she can carry out all normal activities throughout the period of stimulation.
The eggs are collected from the ovaries using an ultrasound guided probe inserted into the vagina. A needle runs inside the probe and can be gently passed through the vaginal wall into each ovary in turn, allowing the doctor to aspirate eggs from the ovary. The procedure is usually carried out under light general anaesthetic or with sedation. You can go home 1 -2 hours after the procedure and are advised not to drive and to rest for the reminder of the day.
Once in the laboratory, the eggs undergo a freezing procedure called vitrification. This involves rapid freezing the eggs using a process that extracts fluid from the eggs to prevent potentially damaging ice crystal formation. Once vitrified, eggs may be stored for many years.
- Egg freezing success rates
Vitrification for egg freezing is a relatively new procedure and it is too early to be able to give precise figures for the chance of pregnancy after freezing, future thawing and fertilisation. The chance of success is largely determined by the woman’s age at the time of freezing.
Currently we would expect the success rates for egg freezing would be
- for a woman aged 35 or under, one stimulated cycle would result in the collection of 10 – 12 eggs of which 7 – 9 would be suitable for vitrification and storage
- Approximately 80-90% of eggs would survive warming in the future
- Approximately 50-80% of surviving eggs would fertilise
- Approximately 80-90% of fertilised eggs would develop into embryos
- A single embryo would have a 20-35% change of developing into a pregnancy
Success rates are lower for women over 35 and egg freezing in women over the age of 38 is unlikely to lead to a pregnancy.
The expected success of the procedure can be ascertained from an initial assessment of the ovarian reserve using a blood test for Anti-Mullerian Hormone (AMH) and an ultrasound scan of the ovaries and uterus. The AMH test can provide insight into the quantity of eggs remaining, although it does not give information about the quality of the eggs.
Egg freezing cannot ever be guaranteed to lead to a pregnancy and birth of a healthy baby later in life. Women who freeze their eggs may not know the outcome for many years and may lose the opportunity to have a baby naturally.
- Can you freeze your eggs if you have low AMH?
Egg freezing is a reasonable option for younger women with low AMH levels. They would be expected to have good egg quality because of their age and may be advised to freeze eggs as they may run out of their store of eggs earlier than usual.
- How much does it cost to freeze your eggs?
In Australia, Medicare and other government subsidies are only payable for fertility treatment when there is a medical indication. Cycle costs are dependent on your circumstances. Please call our Public Liaison Advisor on 1800 111 483 or send an enquiry below to discuss further.
- Who might consider egg freezing?
You might consider egg freezing
- if your fertility is at risk from a serious illness such as cancer;
- or because you are not in a position to have a baby right now and would like the opportunity to start a family beyond the age at which fertility naturally declines.
If you are contemplating egg freezing you should consider other options which may be available to you, such as embryo freezing, donor insemination (for more immediate rather than delayed pregnancy) or the possible use of donor eggs if your own ovarian function is likely to be lost.
Want to find out more?
To find out more about egg freezing please book an appointment with a fertility specialist on 1800 111 483 or complete the form below.