Preserving fertility in women with cancer
Although cancer incidence rates in women less than 50 years of age continue to increase during recent years, mortality rates are dramatically decreasing due to modern advances in cancer treatment. In 1990 the incidence of cancer survivors was 1 in 1,000 for young adults (15–45 years of age) and by 2010, as many as 1 in 250 patients in this age group would have survived cancer. However, increasing numbers of survivors are now confronted with the long-term consequences of exposure to these cancer treatments. Cancer therapy such as surgery, radiotherapy, and chemotherapy, can have a profound impact on ovarian function, leading to premature menopause and loss of fertility.
You can use this information to learn more and then discuss your fertility options with your doctor. Be sure that you understand the risks and chances of success of any fertility preservation option you are interested in, and keep in mind that no method works 100% of the time. Fertility preservation options can be offered to both married and single women. Even married women should be aware that embryos created with a husband are often unable to be used if a divorce occurs. The best option for a woman to have control over her future fertility is to freeze unfertilized eggs or ovarian tissue.
How does chemotherapy affect fertility in women?
Most chemotherapy drugs (medicines to destroy cancer cells) can damage a woman’s eggs (ovarian follicles), affecting her fertility. This affect will depend on the woman’s age, the types of drugs she gets, and the drug doses.
Chemotherapeutic drugs that can cause egg damage and infertility are Carboplatin, busulfan, carmustine (BCNU), chlorambucil, cisplatin, cyclophosphamide, doxorubicin/adriamycin, ifosfamide, lomustine (CCNU), mechlorethamine, melphalan, procarbazine, temozolomide. There are also some chemo drugs that have a low risk of damaging the eggs such as 5-fluorouracil (5-FU), bleomycin, cytarabine, dactinomycin, daunorubicin, fludarabine, gemcitabine, idarubicin, methotrexate, vinblastine, vincristine. Talk to your doctor about the chemotherapeutic drugs you will get and their fertility risks.
What should I know about chemotherapy & pregnancy?
- Age at the time of chemotherapy makes a difference: The younger you are, the more eggs you will have in your ovaries. Even though chemotherapy can damage some eggs you will have a large reservoir of eggs hence a higher chance to keep some fertility. Women who are treated for cancer before the age of 35 years have the best chance of becoming pregnant after treatment. Sometimes, women in their teens or early twenties never stop having menstrual periods even after chemotherapy. Sometimes when young women who stop having menstrual periods during chemotherapy treatment may have normal menstrual periods again after they are off chemo for a while.
- After chemotherapy, fertility may be of shorter duration: When young girls who had chemotherapy before puberty (the time when periods begin) or young women whose menstrual periods have restarted after chemotherapy are at risk for early (premature) menopause. The average age for menopause is about 51 years and when a woman stops having their regular menstrual periods before 40 years, it’s considered premature ovarian failure or primary ovarian insufficiency. She becomes infertile because her ovaries stop making the hormones needed for fertility: estrogen and progesterone.
- You need to understand that having regular menstrual periods after chemotherapy doesn’t always mean fertility: Even if a woman’s menstrual periods start back after chemotherapy treatment has stopped, her fertility is still uncertain. Usually, some eggs are destroyed by chemotherapy treatment and the remaining eggs may not be good enough for conception. You may need a fertility expert to help you find out if you are fertile or learn how long the fertility window may last.
- During chemotherapy treatment you need to avoid getting pregnant: You might be fertile during some types of chemotherapy treatment hence you’ll be advised to use very effective birth control methods. Many chemo drugs can harm a developing fetus and can cause birth defects or other abnormalities. Talk to your doctor to know more about this. It’s important to remember that some women can get pregnant even when their periods have stopped, so you need to use birth control methods whether or not you have periods.
- If you get pregnant immediately after chemotherapy, it can harm the baby: Women are often advised not to get pregnant within the first 6 months after chemotherapy because the medicine might have damaged the eggs that were maturing during chemotherapy treatment. If a damaged egg is fertilized, the embryo could miscarry or develop into a baby with some genetic problem. If you wish to become pregnant please talk to your doctor.
Chemotherapy can affect your fertility, but there are ways to preserve it, discuss with your doctor about options before you start chemotherapy.
Will radiation therapy affect fertility in women?
Radiation treatment is a mode of treatment wherein high-energy rays are used to kill cancer cells. Even with the best radiation machines available along with cancer cells, normal cells in the surrounding gets high-energy rays and get damaged. When radiation is given to the pelvic area these rays can also damage ovaries. High doses of radiation, when used (in cases such as cervical/endometrial/ sarcoma), can destroy some or all of the eggs in the ovaries and can lead to infertility or early menopause. The majority of the women getting radiation to the pelvic area will lose their fertility, but if the ovaries are moved further from the target area by means of minor surgery before radiation begins about 50% may still keep some eggs alive.
Even if the radiation is not aimed right at the ovaries, the radiation rays can travel around inside the body and might still damage the ovaries. In the case of endometrial and cervical cancer radiation is directed inside the vagina. As the vagina is close to the ovaries they absorb a high dose of radiation and can be damaged.
When radiation is directed to the uterus this can cause scarring, which decreases the blood flow to the uterus and this can prevent implantation of the embryo and because of scaring it may also prevent the uterus to stretch to full size during pregnancy, leading to miscarriage or abortions. Such women can have an increased risk of miscarriage, low-birth weight fetuses, and premature births.
Sometimes when radiation is given to the brain it affects the pituitary gland and this pituitary gland normally signals the ovaries to make hormones, so interfering with these signals can affect ovulation (the release of eggs from the ovaries).
It’s very important for you not to become pregnant until treatment is completed because radiation can harm the fetus. If you receive radiation while you are pregnant and especially in the first three months then the fetus has a very high risk of developing anomalies.
Note: If you are pregnant or planning to become pregnant and you have questions about how radiation exposure could affect you or your pregnancy, you should talk with your doctor. Your doctor will help you understand better the risks of radiation exposure to you and to your developing baby.
How will cancer surgery affect fertility in women?
Surgery as part of the treatment for cervical, endometrial or ovarian cancer can cause infertility.
For cervical and uterine cancers, a hysterectomy is part of the treatment. A hysterectomy means surgery to remove the uterus (womb). Every woman has one uterus so when the uterus is removed, she cannot carry a child. As an alternative, very few women have now had babies by having a uterus transplanted into their bodies, but this is a very complicated, risky procedure. After the procedure woman needs to take drugs to suppress her immune system (post-treatment will exactly be like that after kidney or liver transplant). The new uterus must be removed either when the baby is born, or maybe after the completion of the family.
When ovaries are removed it is called oophorectomy, this will be done along with hysterectomy (total hysterectomy with bilateral salpingo-oophorectomy). Without ovaries, a woman can’t get pregnant because she no longer has any eggs.
In some women with early-stage ovarian cancer, we do something known as fertility-sparing surgery wherein we only remove the ovary with cancer and retain the uterus and opposite normal ovary, this procedure is offered only to those women who have very early ovarian cancer.
Some women with very early cervical cancer will be offered a surgery called a trachelectomy, here we remove the cervix and surround tissue called parametrium but leave the uterus and ovary behind so a woman can carry a pregnancy.
Other treatments that can affect fertility in women
Breast cancer: during breast cancer treatment hormonal therapies may be advised, commonly used drug is tamoxifen and during this treatment, women can still get pregnant hence you will be advised to use effective birth control methods because if you conceive while taking tamoxifen fetus can develop birth defects. Other hormone therapies used during breast cancer treatment may prevent ovulation completely since a woman is put into temporary menopause.
It’s always best to talk to your doctor, any possible effects on your sexual function and fertility.
Way to preserve fertility
1. Egg (oocyte) freezing
Egg freezing (or oocyte cryopreservation): The eggs from the ovary are extracted or sometimes a piece of ovarian tissue can be frozen and this is an established method of preserving fertility in women who do not have a partner. This process might also be called egg banking. When the treatment is complete and ready to conceive, the eggs can be thawed, fertilized, and implanted in her uterus.
Another option for women undergoing fertility preservation, especially if a large number of eggs are retrieved, is to freeze half the eggs and fertilize the other half with sperm from a partner or donor and then freeze embryos. The benefit of this is that freezing the embryo is still more efficient than freezing eggs but it allows a woman more flexibility if her relationship status changes or if she wants to avoid having excess frozen embryos.
2. Embryo freezing
Embryo freezing, or embryo cryopreservation, is one of the most established and successful methods of preserving a woman’s fertility. Mature eggs will be removed from a woman’s ovaries and fertilized with partner’s sperms in the lab and the embryos are then frozen. This is called in vitro fertilization (IVF).
This option is suited for women who already have a partner. For IVF procedure various hormonal injection will be given for the ovaries to produce multiple eggs, this procedure may be risky for some women who have rapidly growing cancer or have cancer that is hormonal sensitivity.
3. Fertility-sparing surgery (for ovarian cancer)
This type of surgery can be an option in young women with very early ovarian cancer and when cancer is present only in one ovary. Cancer must be one of the types that’s slow-growing and less likely to spread such as borderline, low malignant potential, germ cell tumors, or stromal cell tumors, typically Grade 1 epithelial ovarian cancers).
Here we remove the ovary with cancer leaving behind the healthy ovary and the uterus (womb). Studies have shown that this does not affect the long-term survival of these women.
4. GnRH agonist treatment (ovarian suppression)
Gonadotropin-releasing hormone (GnRH) agonists are hormonal drugs that can be used to make a woman go into menopause for a short time. The goal of this treatment is to protect ovaries during cancer treatment to protect them from damaging effects. The hope is during treatment eggs in the ovaries are not damaged, so women will resume normal menstrual cycles after treatment. These hormones are usually given as a monthly or once in three months injections starting a couple of weeks before chemotherapy starts. This treatment is given the entire time a woman is receiving cancer treatment.
5. Ovarian transposition
Ovarian transposition means moving the ovaries from its normal anatomical position away from the target zone of radiation treatment. It’s a standard option for girls or women who are going to get pelvic radiation.
“Discuss with your doctor about various options before you start your treatment.”