How does egg freezing work for cancer patients?

Depending on the type of cancer and the treatment you have, your fertility (ability to get pregnant) might be affected. People have their eggs frozen so they can use them in the future to fertilise with either their partner’s sperm or donor sperm so they can get pregnant.  

Once the egg has been fertilised, the embryo would then be transferred back into your body or into the body of a surrogate who would carry your baby for you.  

Even if you have your eggs frozen it doesn’t mean you will definitely have to use them later in life if you want to try for a baby. You may still be able to conceive naturally if your fertility hasn’t been affected by treatment.  

It may be possible to freeze your eggs after you have finished your cancer treatment or if you relapse. This depends on a number of factors like whether you still need it, if you are well enough for the procedure, when you had your last dose of chemotherapy and how many eggs you have left (this is called your ‘ovarian reserve’). Your clinical care team can refer you to a fertility specialist if you want to find out more.  

The process involves stimulating, collecting, freezing and then storing your eggs. This process normally takes about two weeks. Find out more about how the process works:  

Before you start

You will have some tests at the start of the process. This normally involves a pelvic ultrasound and some blood tests for hormones and virology to check for any viral infections. The ultrasound is often done through your vagina so they can see follicles on your ovaries, which hold the eggs. The ultrasound can also be done outside the body by running the probe over your lower abdomen.  

Depending on where you are in your menstrual cycle and how urgently you need to have the egg-freezing treatment, you may be given hormone tablets to start a period.  

Stimulating the ovaries  

Usually, you would produce one egg a month with a normal period. In the egg freezing process you’ll need to inject yourself with hormones to stimulate (encourage) the eggs to grow outside of your normal cycle – you can do these injections at home, you won’t need to go to your doctor’s or the hospital and you can ask someone to help you do this. You can also ask your fertility doctor and nurses for help and advice.  

You’ll need to inject hormones daily for 10 to 14 days to stimulate the ovaries and grow multiple eggs. During this time you’ll also need to have multiple scans and blood tests to check how the eggs are growing and adjust the amount of medication so it’s most effective. Once the eggs are the right size you’ll take a ‘trigger injection’ which will mature and release the eggs ready for collection. This is usually done 36 hours later.  

Egg collection 

The eggs are collected by putting a needle into each ovary through the vagina. This is usually done under sedation and takes about 30 minutes. An ultrasound is used to guide the needle into each ovary. You should be able to go home after the procedure. Some people have cramps or a small amount of vaginal bleeding after this procedure.   

The eggs will be looked at using a microscope and frozen immediately until you’re ready for them to be used. The fertility clinic will be able to tell you how many eggs were collected and frozen.  

You can store your eggs or embryos for up to 55 years, but you will be asked to renew your consent to storage every 10 years. It’s really important that your clinic has your up-to-date contact so you can renew consent every 10 years. If you move house, make sure you let them know. If a clinic cannot contact you then your eggs, sperm and embryos may be disposed of. This is even if you consented for more than 10 years storage. 

If you had eggs or embryos in storage before 1 July 2022 and your consent is due to expire before June 2024, because your eggs have been in storage for 10 years, your clinic has until 30 June 2023 to contact you about reconsenting to store for another 10 years. 

You might not be able to go through the egg freezing process if you’re too unwell and need to start cancer treatment urgently. If the treatment you’re having doesn’t affect your egg count, egg freezing might not be necessary. For some people, their egg count may be too low for egg freezing to work.  

If you haven’t started your period yet, egg freezing might not be possible but there may be other options. If you’re concerned about this you can speak to your care team.