To help boost egg production, fertility drugs are used to stimulate the ovaries to produce follicles (which contain the eggs). The developing follicles are monitored and when they are large enough, they are carefully emptied to collect the eggs that they have produced. They are collected while the patient is under sedation or general anaesthetic.
To freeze the eggs, they are placed in storage in liquid nitrogen.
Egg freezing is still a very new and experimental technique. To date around 2000 babies have been born using frozen eggs worldwide. .
What happens when eggs are frozen?
The procedure for freezing eggs is as follows:
Step 1. Before the freezing and storage of the eggs, clinician will explain the process involved, including the risks. Counselling usually follows this.
Step 2. Screening for infectious diseases, including HIV and Hepatitis B and C is usually a prerequisite.
Step 3. Written consents are taken for storage.
Step 4. Eggs are collected using the same procedure as for conventional IVF.
Step 5. Cryoprotectant (freezing solution) added to protect the eggs when they are frozen.
Step 6. The eggs are frozen either by cooling them slowly or by vitrification (fast freezing and then stored in tanks of liquid nitrogen.
How long can my eggs be stored for?
When couple agrees to freeze their eggs, they should understand the limits on the storage time and keep in contact with the clinic:
The standard storage period for eggs is normally 10 years.
Couple must let the clinic know if they change the address. This is so that they will be able to contact them when the storage period is coming to an end. If they cannot contact the couple when the storage period ends, they may take eggs out of storage and allow them to perish.
What are the risks of freezing eggs?
The usual risks of using fertility drugs apply to the fertility treatment involved. Egg freezing is still a relatively new technique and not all eggs will survive the freezing and thawing process or become fertilized.
It is important that couple take into consideration the risks of this procedure and the likelihood of the eggs surviving the process when deciding whether to store eggs for future use.