We know that being able to bear children is very important to many adult women who have had childhood cancer. So you will have an indepth consultation with a clinical nurse specialist and/or a doctor who specializes in fertility (fertility specialist). The following matters are discussed during this consultation:
- The effect of the treatment on your child's fertility;
- The options for preserving fertility;
- The risks of a treatment for preserving fertility.
Watch the animation video for children about fertility (in Dutch):
The video is sponsored by Theramex Netherlands B.V and partly made possible by
Initiator and project manager: Dr. A.M.E. Bos, gynecologist UMC Utrecht Project team: M.E.M. van der Perk MD, PhD student of oncofertility I.M. IJgosse, oncofertility nurse specialist Members of the Princess Maxima Center Fertility Working Group S.L. Brother, gynecologist UMC Utrecht Design and animation: Marloes van Loon, www.marloesvanloon.nl
With thanks to (voice-over) Maan, ambassador Princess Máxima Center.
Damage to egg cells
Your daughter's two ovaries are positioned in the lower part of the abdomen, to the left and right of the uterus. They contain her lifetime supply of egg cells. Every month, starting at puberty, one of the immature egg cells develops into a mature egg cell. If it is not fertilized, menstruation occurs. The total number of egg cells declines every year. When the supply of egg cells is depleted, a woman enters menopause. Chemotherapy and radiation can damage mature and immature egg cells. The body expels these damaged egg cells. The number of egg cells decreases at a faster rate and your daughter may enter menopause at a younger age. How many egg cells are damaged depends on the type and dose of chemotherapy and the dose and location of radiation.
Fertility preservation
There are two ways to preserve fertility. In some instances, both approaches are combined (between the ages of 16-18).
Ovarian tissue can be frozen and stored for a very long time. The Princess Máxima Center offers girls who have a high risk of becoming infertile the standard option of freezing ovarian tissue. During keyhole surgery, one ovary is removed from the abdomen. This ovary is divided into small pieces and then frozen. Should your daughter become infertile and at some stage want to bear children, the pieces are thawed out and returned to her body.
Since 2004, more than 150 children around the world have been born to adult women after this treatment, of whom six in the Netherlands. The chance of bearing a child is about 30% each time ovarian tissue is replaced. No figures about the outcomes of this method in children are available as yet.
There is a small chance of cancer cells occurring in the ovarian tissue. These cancer cells can be returned to the body along with the ovarian tissue. Much research is conducted around the world into the safe use of frozen ovarian tissue. We hope that we can safely use the ovarian tissue in the future.
Important to know
- Cancer treatment does not have to be delayed.
- Freezing and storing ovarian tissue is only possible if it is highly likely that the treatment will make your daughter infertile.
- The replacement of ovarian tissue is still experimental and is only done in the context of research.
Removing the ovary
The fertility specialist removes one of the ovaries during keyhole surgery under anesthesia in the surgery department in the Wilhelmina Children's Hospital. We try to combine this surgery with another procedure under anesthesia, such as placing a line or taking a biopsy, in which case the operation takes 20-30 minutes longer. Chemotherapy can start soon after surgery.
Possible complications
- There are occasions that keyhole surgery has to be terminated because of adhesions in the abdomen.
- Sometimes the urinary tract, intestines or blood vessels are damaged.
- There is a small risk of infection or thrombosis.
- In the event of a complication, the cancer treatment must sometimes be postponed.
Freezing and storing
The ovary is divided into small pieces in the fertility laboratory. These pieces are frozen. Frozen egg cells can be stored for many years. Replacement If your daughter is infertile and at some stage in her life wants to bear a child, the frozen ovarian tissue can be thawed out and placed in the remaining ovary or elsewhere in the abdomen.
If your daughter is 16 years of age or older, her egg cells can be frozen. She first undergoes hormone treatment to enable several egg cells to mature. These mature cells are frozen and stored. If your daughter has become infertile as a result of the treatment and at some stage wants to become pregnant, her egg cells are thawed out and fertilized with a sperm cell. The resulting embryos are then placed in her uterus.
There is no guarantee that your daughter will bear a child with this method. The chance of pregnancy is approximately 5% per frozen egg cell. This means that approximately 20 egg cells are required for a pregnancy. So far, no more congenital anomalies have been detected in children who are born after their mother's egg cells have been frozen, than in other children.
Important to know
- Girls' egg cells can be frozen as from the age of 16.
- The hormone treatment takes at least two weeks and can only take place if there is enough time before cancer treatment commences.
- The egg cells can be used up until your daughter is 50 years old.
- To date, there seems to be no higher risk of (congenital) anomalies in children born from frozen egg cells.
Hormone treatment and harvesting
Treatment takes place at the UMC Utrecht. Normally, only one egg cell matures every month. More than two weeks of daily hormone injections ensures that more egg cells mature at the same time. This enables us to harvest multiple egg cells. The hormone injections are administered at the pharmacy in the UMC Utrecht. We use an ultrasound to see how the egg cells are developing. Once big enough, they are harvested. Harvesting occurs under sedation or anesthesia. The egg cells are frozen and stored. Several hormone treatments are required to be able to store enough egg cells.
Possible complications
- There is a very small chance of bleeding or infection.
- Your daughter may not feel well and suffer from bloating, stomachache and shoulder pain.
Freezing and storing
The egg cells are frozen and can be stored for many years.
Thawing and fertilizing eggs
If it turns out that your daughter is infertile and at some stage wishes to bear children, the egg cells can be thawed and fertilized with a sperm cell, after which the fertilized egg cell is placed in the uterus. This is possible up until your daughter is 50 years old.
The result of this treatment is still uncertain. Only after thawing will we know how many eggs have survived and whether they can be fertilized. This means that there is a chance that your daughter will not become pregnant. There is therefore no guarantee that she will bear a child.