Ovarian Tissue Cryopreservation

Information for parents / carers

Contents

1. The role of cryopreservation
2. FAQs
3. The procedure
4. What happens next?
5. Contacts/Further Information

Who is the leaflet for?

This information is for parents/carers of patients eligible for ovarian tissue cryopreservation as part of treatment with the Paediatric Haematology and Oncology department at Cambridge University Hospitals.

1. The role of ovarian tissue cryopreservation

Recent years have seen many advances in treating conditions affecting children and young adults. Some of these treatments may have a negative effect on a person’s fertility and could prevent them from being able to have children in the future. These treatments include, but are not limited to, cancer therapies (chemotherapy and/or radiotherapy) and bone marrow/stem cell transplant. Standard ways of preserving fertility, such as sperm and egg storage are not always possible for children and young adults. We are now able to remove and store (cryopreserve) testicular or ovarian tissue to preserve a young person’s fertility for future use.

2. Frequently Asked Questions about ovarian tissue cryopreservation

What is ovarian cryopreservation?

Girls usually have two ovaries situated either side of their womb. The ovaries produce eggs and hormones such as oestrogen. When girls are born, their ovaries contain over a million immature eggs, and over time the number of eggs naturally falls until they reach the menopause in later life. Certain treatments mean eggs are lost at a faster rate which can cause problems with fertility and/or premature menopause. Ovarian tissue, containing its immature eggs and hormone function, can be stored using a special freezing technique called cryopreservation which safely preserves and stores human tissue at very low temperatures (-170°C).

Does ovarian tissue cryopreservation work?

Ovarian tissue cryopreservation programmes have been running across the world since the early 2000s. More than 150 babies have now been born using ovarian tissue that has been cryopreserved. Success rates are similar to standard fertility treatments such as in vitro fertilisation (IVF). Although this treatment remains relatively new, results are extremely promising.

Where does ovarian cryopreservation take place?

The procedure to retrieve ovarian tissue will take place in your local children's surgical unit at Addenbrooke’s Hospital. The tissue will be specially transported to our partners at the Oxford Cell and Tissue Biobank (OCTB), England’s specialist centre licensed for preserving and storing this type of human tissue.

How will ovarian tissue be collected?

Ovarian tissue is collected by removing one of the ovaries during a short surgical procedure. This procedure is often a keyhole operation (known as a laparoscopic oophorectomy), performed under general anaesthetic through three small wounds on the abdomen (tummy). During the operation, the surgeon will check whether both ovaries are present and look normal before removing one to preserve, leaving the other in place. Occasionally, it is not possible to safely remove the ovary with a keyhole technique, if this is the case, a small additional wound will be made to allow ‘open’ removal. In some planned cases, if your child requires surgery on their abdomen as part of their treatment, where possible the ovary will be removed at the same time using the same wound. The tissue is immediately put into a special preservative fluid before being transferred to the OCTB and frozen.

Will this increase the risk of premature ovarian failure (menopause)?

No – studies have shown that women born with only one ovary or who have had an ovary removed will start menopause at the usual age if their remaining ovary functions normally. However, premature ovarian failure could develop as a side effect of your child’s other treatments. Current research suggests that this may be helped by returning some of the stored ovarian tissue in the future.

3. The procedure

Before the procedure

Your medical team has suggested that this procedure may be helpful for your child to preserve their future fertility. You will be offered a telephone call with a specially trained clinical nurse specialist (CNS) who will explain the process in more detail and can assist you with any questions you may have. The CNS will be present for the procedure and will ensure that the tissue is transferred safely for freezing.

If you wish to proceed, you will have a telephone conversation with a member of Future Fertility Preservation, Oxford (FFPO), who will discuss the next steps in more detail and give you a further opportunity for questions. They will ask you to sign a consent form for the transfer, freezing and storage of the tissue.

Before admission to hospital

You will be contacted with a date for surgery and information regarding starvation times and any tests which may need to be carried out before your child’s admission.

• Purchasing suitable painkillers

It is important that you purchase some children’s paracetamol (for example Calpol) before admission to hospital so that you have this available at home after discharge. If it is likely that your child will need ‘stronger’ pain killers, these will be supplied via the hospital. Please ensure you follow your team’s advice regarding paracetamol use and contact them using the telephone numbers provided if you have any concerns or questions about this.

• If your child becomes unwell

If your child has a cold, cough or illness such as chicken pox the operation may need to be postponed to avoid complications. Please telephone us (the telephone number is provided at the end of this leaflet) to discuss this, prior to coming to hospital.

• Starvation times

Your child will not be able to eat and drink before the operation. Specific advice about this will be given on your booking confirmation letter or discussed with you over the telephone.

Admission to hospital

Depending on your child’s needs, you will be asked to bring your child to one of the children’s wards. You will be seen by nursing staff, surgeons (who perform the operation) and an anaesthetist (who puts your child to sleep for the operation). You will meet your clinical nurse specialist who will collect the cryopreservation consent form, and your surgeon who will ask you to sign a further consent form to give permission for the surgery to remove the tissue.

When it is your child’s turn for surgery, you will be moved from the ward to the anaesthetic room of the operating theatre where your child will be checked in, and the procedure confirmed with you once more. Your child will then be given medicine to go to sleep before being taken into the operating theatre. You can remain by your child's side while they go to sleep. The operation time may vary, but you will be given a pager so that you are alerted when it is complete.

In most cases surgery will be carried out as a ‘day case’ procedure, meaning you will be able to arrive on the morning of surgery and leave the same day. In some planned cases, this procedure may be combined with other procedures which your child may need. If your child needs to stay in hospital overnight a bed will also be provided for a parent to also stay.

Complications

Complications from this procedure are rare, but may include:

• Infection
• Bleeding
• Adhesions, strings of scar tissue which may form inside the abdomen
• Injury to nearby structures
• Incisional hernia – a small lump at the keyhole wound site
• Very rarely, the sample taken is inadequate and cannot be used for cryopreservation

These will be discussed and explained in more detail to you by the surgical team when you meet in person and before you sign the consent forms for the procedure.

After the procedure

• Your child will be given local anaesthetic to numb the wound and to make them more comfortable when they wake up.
• The wound will be closed with sutures (stitches) and/or skin glue. These sutures will dissolve over time and you will not need to have them removed.
• Most children will be able to go home on the same day as their operation after they have had a drink, something to eat and have passed urine.
• We advise that your child wears loose fitting clothes for the journey home and for a few days after the operation to prevent discomfort.
• They may feel sore around their wound for the next few days. This can be managed with paracetamol following the guidance given to you by your team.
• It is common for some swelling and/or bruising to develop within 24 hours of the operation and this may take a few weeks to settle down.
• Please keep the wound clean and dry for five days.
• Your child will require a set of blood tests. We are required to test after the procedure, in a Human Tissue Authority licensed laboratory.
• You will be sent a letter with a copy of your tissue bank consent form, information about how your tissue is being stored and how to access it when the time comes. There will also be contact information in this letter should you have any further questions or concerns.

Looking after your child at home

• The wounds should be kept clean and dry, but not submersed in bath water for five days to help prevent infection. If the wound gets soiled (for example covered with faeces/’poo’) you should shower your child or allow a quick dip into clean bath water to clean the area.
• Where a dressing has been applied, this may fall off on its own or can be soaked off during the first bath at day five after surgery.
• Where applicable, nappies should be changed regularly to keep urine away from the wound areas.
• Check the wounds for signs of infection - If it starts to appear red, seek advice from your GP.

4. What happens next?

What will happen if you want to use your tissue in the future?

If/when your child decides they wish to use their stored ovarian tissue, they will need to contact the tissue bank. They will then be offered an appointment with one of the senior medical staff working with FFPO to discuss the most appropriate treatment options. Any future procedures will be fully discussed along with a separate consent process for any use of tissue.

Is there a risk that the tissue could contain cancer cells?

Prior to storage the ovarian tissue collected will be screened for cancer cells by standard methods. If/when your child wishes to use the stored tissue, a sample would first be rigorously tested using the most advanced techniques available at the time. Options for how the tissue may be used will be dependent on the most up to date research at the time they wish to use it. Research is ongoing and therapies may well be more advanced by the time your child wishes to explore using this tissue. The FFPO team will be able to advise on the most up to date techniques as they become available.

What happens when you no longer require tissue?

The tissue stored will be for your child’s use only; it can never be used for any other patient. When your child no longer requires the tissue it will either be destroyed by incineration or, if you/they wish, it will be used for ethically approved research. You will have the opportunity to discuss all relevant options in detail before signing the appropriate consent form.

Chaperoning

During your child’s hospital visits they will need to be examined to help diagnosis and to plan care. Examination, which may take place before, during and after treatment, is performed by trained members of staff and will always be explained to you beforehand. A chaperone is a separate member of staff who is present during the examination. The role of the chaperone is to provide practical assistance with the examination and to provide support to the child, family member/carer and to the person examining your child.

5. Contacts/Further information

If you have further questions or would like more details, please call the Paediatric Haematology and Oncology Clinical Nurse Specialist team on 01223 216485.