Fertility Problems

Some forms of cancer treatment can affect a man's ability to father children or a woman's ability to become pregnant (fertility). Infertility is the inability to conceive a child. Infertility can occur:

• when the testicles stop producing sperm cells
• when a woman's supply of eggs (ova) is low or has run out
• if the reproductive system is damaged

Infertility may be temporary or permanent and depends on several factors:

• the person's age
• the person's fertility status before they had treatment
• the area being treated
• the type and dose of treatment
• the length of time since treatment

Cancer treatments affecting fertility

Surgery

Some surgeries for cancer can cause a permanent loss of fertility. Infertility occurs when reproductive organs are removed.

• If both testicles are removed, the man no longer produces sperm. If the prostate is removed, the man no longer produces any semen. Surgery that damages the nerves supplying a reproductive organ such as the prostate can cause erectile dysfunction (impotence), which can also affect fertility.
• If a woman's ovaries are removed, she will not make any eggs (ova) that can be fertilized by sperm. If a woman's uterus is removed, she will not have a womb in which an unborn baby (fetus) can develop and grow.

Radiation therapy

Radiation therapy can impair sexual function in men or women. This happens if the treatment area includes the pelvis or reproductive organs and the testes or ovaries receive enough radiation to cause damage. The more radiation the testes or ovaries are exposed to, the greater the chance these organs may fail to function.

Depending on the total dose of radiation given to the pelvic area:

• Radiation to the testicles can reduce the number of sperm and affect the sperm's ability to function.
• Radiation for prostate cancer may affect a man's ability to have an erection and cause erectile dysfunction (impotence).
• Radiation can cause irreversible damage to a woman's ovaries (including the eggs) and result in a permanent loss of reproductive function and menopause (treatment-induced menopause).

Chemotherapy

Chemotherapy drugs kill rapidly dividing cells throughout the body. Not only do cancer cells divide rapidly, but so do sperm cells in men and the cells surrounding the ripening eggs (ova) in women. So some chemotherapy drugs or combinations of drugs can damage the ovaries or testicles and result in infertility. The type of drug(s), dose and number of drugs used will influence whether fertility will be affected or not.

• Many types of chemotherapy drugs can decrease sperm production and affect sperm counts in men.
• Most chemotherapy drugs can affect a woman's menstrual cycle, causing a woman to stop ovulating (ovarian failure). This can result in premature menopause. Menopause and loss of ovarian function may be permanent. Younger women (less than 35 years old) may regain ovarian function. Women older than 35–40 years of age are less likely to regain ovarian function, which will result in infertility.

It is difficult to predict if sperm or ovarian function will be affected, because the effects of chemotherapy vary from person to person. Although chemotherapy can damage the eggs and destroy the sperm-producing cells, some of these may not be damaged. They will continue to function when the person is off treatment and fertility may return. Usually younger men and women have a better chance of regaining fertility. Younger women also have a larger reserve of eggs, because as a woman ages, her supply of eggs decreases.

Several chemotherapy drugs have the potential to affect fertility. Drugs called alkylating agents have the most damaging effects on fertility. Examples of some drugs that may affect fertility include:

Hormonal therapy

Some hormonal therapies may block the effects of necessary reproductive hormones such as estrogen or testosterone and can impair fertility.

Fertility and parenthood options

People concerned about the effects of cancer treatment on their ability to have children should discuss this with their doctor.

Fertility counselling

Fertility counselling should be done before treatment is started. Counselling can help cancer patients and their partners become aware of and discuss:

• options available
• which options may be appropriate
• future implications
• costs associated with the options

Some people may be infertile because of their cancer when they are diagnosed, so some options will not be appropriate.

Medical procedures done to deal with infertility and help couples conceive may be called assistive reproductive technology (ART). The rates of a successful pregnancy vary depending on the method used.

Radiation shielding

Fertility may be preserved by radiation therapy techniques and lead shielding to protect reproductive organs. Whether this will be possible or not depends on the type and location of the cancer. When possible, the testicles in men and the ovaries in women are shielded during radiation treatments.

Sometimes women may have surgery to move the ovaries out of the radiation field (oophoropexy or ovarian transposition) before radiation therapy. By moving the ovaries out of the treatment area (and behind the uterus or closer to the pelvic bones), the ovaries may be protected and allow a woman to maintain fertility.

Sperm banking

Some men may wish to freeze sperm (sperm banking) before treatment is started, in case the sperm count does not return to normal after treatment and they wish to father children in the future. The sperm is collected (a few semen collections are recommended), frozen and stored for future use in fertilization procedures known as artificial insemination:

• intrauterine insemination
  • Banked sperm is inserted into the woman's uterus after ovulation.
• in vitro fertilization (IVF)
  • The woman's egg and the man's sperm are brought together in a test tube in the laboratory (in vitro). The fertilized egg (embryo) is later implanted into the woman's uterus.
• intracytoplasmic sperm injection (ICSI)
  • A single sperm is injected into a single egg and later implanted into the woman's uterus.

Embryo freezing

Some women may wish to look at the possibility of storing fertilized embryos. The woman's eggs are removed during a surgical procedure and fertilized with the partner's sperm. The fertilized eggs are then frozen and stored (cryopreserved) so that they may be reimplanted in their uterus at a later date. To increase the number of mature eggs available for collection, hormone injections are often used.

The type of cancer, how quickly cancer treatment needs to be started and other factors may make this approach unsuitable.

There are other fertility options being studied that may help preserve a person's fertility.

Other parenthood options

Some cancer patients and their partners may wish to look at alternatives to having their own children after treatment such as:

• adoption
  • Having cancer does not rule out the possibility of adoption, but some agencies may require that a certain amount of time pass after a person's treatment before adopting. Agencies may also require doctor's approval.
• surrogacy options
  • Another woman carries and bears the child for potential parents. This is an option if a woman's uterus has been removed because of cancer.
• using donor sperm or eggs
  • The egg donor may be anonymous or known to the couple. Sperm donors are mostly anonymous and only frozen sperm are used.

Some of these options may not be available in all provinces: Check with provincial health insurance plans about coverage for fertility options, because some methods may not be covered. Check with adoption agencies or seek legal advice on adoption or surrogacy parenting.