The effects of cancer treatment on women’s fertility

Here we provide an overview of cancer treatments and how they affect women’s fertility. The most common treatments for cancer are chemotherapy, radiation therapy, surgery and hormone therapy. Other treatments include immunotherapy and targeted therapy.

Find out more about chemotherapy, radiation therapy and surgery, or call Cancer Council 13 11 20.

Learn more about:

• Chemotherapy
• Radiation therapy
• Surgery
• Hormone therapy
• Other treatments
• Avoiding pregnancy during treatment
• Fertility outcomes

Listen to our podcasts on Making Treatment Decisions, Sex and Cancer and Coping with a Cancer Diagnosis

Chemotherapy

Chemotherapy uses drugs to kill or slow the growth of cancer cells. These are called cytotoxic drugs and they are designed to affect fast-growing cells such as cancer cells. This means they can also damage other cells that grow quickly, such as the reproductive cells.

The risk of infertility depends on several factors:

• the types of chemotherapy drugs used – damage to eggs is more common with chemotherapy drugs in the alkylating class
• the dose and duration of chemotherapy treatment – the risk increases with higher doses and longer treatment times
• your age – the number and quality of eggs start to decline naturally as a woman gets older.

Chemotherapy can cause some women’s periods to become irregular, but they often return after treatment ends. For other women, periods may stop, which will bring on menopause. After menopause, women can’t conceive children with their own eggs. For more on this, see Fertility outcomes.

Some chemotherapy drugs can also affect your heart and lungs.

If the drugs cause long-term muscle damage, this may complicate a future pregnancy and delivery. Your specialist will talk to you about what precautions to take during pregnancy.

Radiation therapy

Radiation therapy (also called radiotherapy) uses x-rays to kill cancer cells or damage them so they cannot grow and multiply. It can be delivered externally by external beam radiation, or given internally.

The risk of infertility will vary depending on the area treated and the dose of the radiation therapy.

• External or internal radiation therapy to the pelvic area (for cancer of the rectum, bladder, cervix or vagina) can stop the ovaries producing hormones. This results in temporary or permanent
• Treatment to the pelvic area can increase the risk of miscarriage, premature birth and low birth
• Radiation therapy to the brain may damage the pituitary gland, which releases hormones that stimulate the ovaries to release an egg each month.

Surgery

Surgery that removes part or all of the reproductive organs, such as the ovaries, fallopian tubes, uterus and cervix, can cause infertility.

Removal of the uterus and cervix (hysterectomy)

This may be used to treat gynaecological cancers, such as cancer of the cervix, ovary, uterus and endometrium (lining of the uterus), and sometimes, cancer of the vagina. After a hysterectomy, you will be unable to become pregnant and your periods will stop.

Removal of the ovaries (oophorectomy) 

If both ovaries are removed (bilateral oophorectomy) and you haven’t already been through menopause, you will experience early menopause. You will no longer have periods or be able to become pregnant naturally.

Removal of the whole bladder (radical cystectomy)

If bladder cancer has spread to the abdominal area, the urethra, uterus, ovaries, fallopian tubes and a part of the vagina are often removed. If you have not yet gone through menopause, this will cause your periods to stop and you will be unable to have children naturally.

Hormone therapy

Hormones are naturally produced in the body; however, they can cause some types of cancers to grow. The aim of hormone therapy is to slow down the growth of the cancer.

A hormone receptor is a protein on a cell. Hormone therapy is used for women who have hormone receptors on their cancer cells. This means the growth of cancer cells is affected by the female hormones oestrogen and progesterone. Cancer cells with hormone receptors on them are said to be hormone receptor positive. There are two types of hormone receptors: oestrogen receptors and progesterone receptors.

Hormone therapy blocks the hormones that are required for fertility, so you will have to wait to try for a baby. However, it may be possible to store eggs or embryos before hormone therapy – learn more about this process.

Anti-oestrogen drugs (such as tamoxifen, goserelin and aromatase inhibitors) are used to treat oestrogen-sensitive cancers to reduce the risk of recurrence. Many anti-oestrogen drugs are taken for several years. During this time, pregnancy should be avoided, as there is a risk the drugs could harm an unborn child.

Other treatments

Stem cell transplants, immunotherapy and targeted therapy are other ways of treating cancer.

Stem cell transplants often require high doses of chemotherapy and, possibly, radiation therapy. These are given before the transplant to destroy cancer cells in the body and weaken the immune system so that it will not attack a donor’s cells during the transplant. The risk of infertility after high-dose chemotherapy or radiation therapy is high.

The effects of immunotherapy and targeted therapy on fertility and pregnancy are not yet fully understood. Early research suggests some targeted therapy drugs can cause early menopause.

It is important to discuss your fertility options with your cancer treatment team or fertility specialist.

Fertility outcomes

Some women are able to conceive after cancer treatment without medical assistance. However, about one in three women will experience one of the following issues.

Acute ovarian failure

During treatment, and for some time afterwards, the ovaries often stop producing hormones because of the damage caused by the cancer treatment. This is known as acute ovarian failure. It is often temporary, and you will have occasional or no periods, and symptoms similar to menopause. If ovarian failure continues for a number of years, it is less likely that your ovaries will work normally again.

Early menopause

Menopause before the age of 40 is known as early menopause or premature ovarian insufficiency (POI). This is when you stop having menstrual periods because egg numbers are very low.

The eggs may have been destroyed or damaged by treatment. If too many eggs are damaged during treatment, menopause is permanent. Early menopause could occur immediately or many years after treatment depending on your age, type of treatment and dose.

While menopause means you won’t ovulate, it is still possible to carry a baby if you have a uterus and use stored eggs or donor eggs. A small number of women with POI (5–10%) have a chance of becoming pregnant naturally, because in some rare cases, a remaining egg may mature and be fertilised by a sperm.

It feels like menopause is discussed as a treatment side effect, not as this massive impact on who you are as a person. I’m facing menopause 20 years earlier than my friends.

  — Denise

Symptoms of early menopause may include:

• a dry or tight vagina
• a loss/reduction of interest in sex (low libido)
• hot flushes and night sweats
• pain in joints
• problems falling asleep and staying asleep
• feeling more anxious or

The symptoms are usually more severe when menopause starts suddenly, because the body hasn’t had time to get used to the gradual decrease in hormone levels.

There are various ways to manage the symptoms of menopause.

Early menopause can also cause the bones to weaken (osteoporosis). Talk to your doctor about having a bone density test or taking medicines to prevent your bones weakening. Osteoporosis Australia has more information – call 1800 242 141 or visit osteoporosis.org.au.

Talk to your doctor about the benefits and risks of hormone replacement therapy (HRT). This replaces the hormones usually produced by the ovaries, and can be taken as tablets, creams or skin patches.

Taking HRT containing oestrogen may increase the risk of some diseases. Ask your doctor whether it is safe to use. Some women with a hormone-sensitive cancer may be advised not to take HRT. Vaginal moisturisers available over the counter can help with vaginal discomfort and dryness.

Non-hormonal options, such as acupuncture, can also help. Taking calcium and vitamin D tablets, and performing some weight-bearing exercises to strengthen the bones, can relieve some menopausal symptoms. Exercise can also help with mood changes and energy levels, and will help keep your bones strong. Discuss the best options for your situation with your doctor.