You may be able to take certain steps and precautions to preserve fertility before, during and after treatment.
Options to preserve eggs before treatment
Egg or embryo cryopreservation (freezing). A person assigned female at birth who either has gone through puberty or is currently going through it can freeze their eggs. Puberty usually occurs between the ages of 9 and 15. During the procedure, eggs are removed from the ovary to be frozen and stored for possible use in the future. They can be frozen either as unfertilized eggs (oocytes) or as eggs fertilized with sperm (embryos). These procedures are performed by trained specialists called “reproductive endocrinologists.”
- Egg freezing. To stimulate the ovaries and encourage eggs to mature, the patient receives daily hormone injections for about 10 days to stimulate the ovaries. The patient is given an anesthetic, and the eggs are then removed from the ovaries and frozen for future use without being fertilized. The entire process generally takes about 2 to 3 weeks to complete. Doctors can usually start an egg freezing cycle at any time, regardless of the stage of the menstrual cycle using “random start” stimulation protocols.
- Sometimes it is necessary to begin cancer treatment right away, which does not allow time for hormone fertility treatment. Or, hormone fertility treatment may not be safe or appropriate for some patients. In these cases, immature eggs may be collected from the ovaries after only brief fertility treatment or without fertility treatment. (Immature eggs can also be collected from surgically removed ovarian tissue.) Since these eggs will not have fully matured in the ovaries, the eggs must then undergo in vitro maturation (IVM), which means that the eggs will mature in a laboratory. Researchers are still learning about IVM and success rates are lower than when freezing mature eggs.
- Since egg freezing does not require sperm at the time of collection, it is a good option for patients who may be undecided about family plans and do not want to use donor sperm to fertilize their eggs. It is also a choice for those who have religious or ethical objections to embryo freezing.
- Embryo freezing. After the egg retrieval process (see above), the eggs are fertilized in the laboratory with sperm from a partner or donor to create embryos. This is called “in vitro fertilization (IVF).” The embryos are then frozen and stored for possible future use. Embryo freezing is the option with the highest likelihood of success. The process can typically take about 2 to 3 weeks.
Patients who have an aggressive cancer requiring immediate treatment may not be able to delay treatment for 2 weeks to complete egg or embryo freezing. Patients with hormone-sensitive cancers should speak with their doctor about the safety of egg/embryo freezing. In some cases, medication can be given to reduce estrogen levels.
Ovarian tissue freezing. Freezing ovarian tissue for later transplantation may be an option. Part of the ovary (or the entire ovary) is surgically removed and frozen for possible future use. This procedure may be appropriate for:
- Patients who have not gone through puberty, and therefore, have no mature eggs
- Patients who need to start treatment quickly
- Patients for whom hormone fertility treatment may be unsafe, such as those with a history of hormone-driven cancers
At the time of removal, the tissue is evaluated for evidence of cancer. The outer layer of the ovary that holds the eggs is removed, cut into small pieces and frozen. In the future, the ovarian frozen tissue containing eggs can be transplanted back into the patient with hope that the eggs will mature. The patient may be able to conceive through natural conception or require IVF.
The first live birth using this method was in 2004 and since then, about 200 babies have been born, mostly from patients who were adults at the time of tissue freezing. Due to the increasing success, it is no longer considered experimental and is a standard option for fertility preservation. For patients with some types of cancer, the doctor may advise against tissue freezing because of a concern that the transplanted tissue could carry cancer cells back into the body. This method is also not recommended for carriers of BRCA gene mutations.
Researchers are also studying using in vitro maturation (IVM) for immature eggs taken from frozen ovarian tissue without having to transplant the tissue back into the body. This is still an experimental approach and further research is needed.
Ovarian tissue freezing is available both outside of clinical trials and as part of clinical trials. If you are interested in clinical trials, talk to your treatment team.
Ovarian transposition (oophoropexy). If the ovaries will be in the radiation treatment field, patients may undergo this minor surgical procedure in which a doctor moves the ovaries outside of the radiation field to minimize exposure and radiation damage. Even when the ovaries are moved, they may still be exposed to some radiation.
Ovarian shielding. A shield can be used to protect the ovaries and other parts of the reproductive system during radiation therapy. Shielding must be planned before treatment begins, and the shields must be used every day of treatment. Not all patients will be able to use shields, because sometimes there is a need to treat the specific area with radiation.
Other considerations before treatment
Uterus transposition. This procedure, done in combination with ovarian transposition, is a new surgical procedure that may be appropriate for patients who need pelvic radiation for certain cancers. If successful, the patient could potentially carry a pregnancy after radiation treatment and possibly conceive without medical assistance. Uterus transposition was first reported in 2017 and is not yet widely available.
Options after treatment
Use of frozen eggs or embryos. If eggs were frozen, they will first be fertilized with a partner or donor’s sperm in the laboratory to create embryos. The embryos are then transferred to the uterus of the person who will carry the pregnancy so pregnancy can occur.
In vitro fertilization (IVF). If a patient has a low egg count (a low ovarian reserve), they may want to consider undergoing an IVF cycle to remove mature eggs to be fertilized with a partner or donor’s sperm in a laboratory. The embryos are then transferred to the uterus of the person who will carry the pregnancy so pregnancy can occur.
In vitro maturation (IVM). If the hormone fertility treatment typically used in IVF is contraindicated for the patient, immature eggs may be collected from the ovaries after only brief fertility treatment or without fertility treatment. (Immature eggs can also be collected from surgically removed ovarian tissue.) Since these eggs will not have fully matured in the ovaries, the eggs must then undergo IVM, which means that the eggs will mature in a laboratory. Researchers are still learning about IVM.
Donor eggs. Eggs donated by another person (who undergoes an IVF cycle) that are fertilized and transferred to the uterus of the person who will carry the pregnancy.
Donor embryos. Embryos are generally donated by couples who have undergone IVF for infertility. If they do not plan to use the embryos, they may choose to donate their remaining embryos rather than discard them.
Related Links
- Download or order The Leukemia & Lymphoma Society’s free fact sheet, Fertility Facts.