Menopause and Cancer Risk

Approved by the Cancer.Net Editorial Board, 04/2016

Menopause occurs when a woman’s ovaries stop releasing eggs.

During natural menopause, the body’s production of estrogen and progesterone hormones decreases. This causes irregular menstrual periods that eventually stop. Women generally start menopause around age 50, but there it may often start earlier or later.

For women with cancer, menopause may begin earlier if treatments cause the ovaries to stop working. This is called premature menopause. Learn more about long-term side effects of cancer treatment.

Menopausal symptoms:

  • Hot flashes

  • Night sweats

  • Fatigue

  • Vaginal dryness

  • Painful sexual intercourse

  • Decreased sex drive

  • Osteoporosis, which makes bones weak and fragile

  • Bladder control difficulties

  • Mood swings and irritability

  • Depression and/or anxiety

  • Sleeping problems, also called insomnia

  • Irregular or heavy menstruation

  • Weight gain

  • Hair loss

  • Food cravings

  • Fuzzy thinking or forgetfulness

Learn how to manage menopausal symptoms.

Menopause and cancer risk

Two main factors are linked with a higher risk of cancer after menopause:

  • Increased exposure to hormones, such as estrogen, which increases the risk of uterine cancer and breast cancer.

  • Increased number of ovulations, which increases the risk of ovarian cancer. Ovulation is the time in a woman’s cycle in which the ovary releases eggs.

As women menstruate longer, they have more ovulations and are exposed to hormones for longer. This means that woman who start menopause after age 55 and/or begin menstruating before age 12 have an increased risk of these cancers.

Research shows that taking oral contraceptives, often called birth control pills, can lower the risk of ovarian cancer. This is because these medications often stop ovulation temporarily. Talk with your doctor about your risk of cancer and the risks and benefits of oral contraceptives.

Menopausal hormone therapy and cancer risk

Combined hormone therapy may help relieve menopausal symptoms, such as hot flashes and osteoporosis. It is also called postmenopausal hormone therapy or hormone replacement therapy (HRT). The treatment is a combination of estrogen and progestin. Progestin is a form of progesterone made in a laboratory.

However, the National Institutes of Health’s Women’s Health Initiative study found that women taking combined hormone therapy to manage menopausal symptoms have a higher risk of these conditions:

  • Breast cancer

  • Heart attack

  • Stroke

  • Blood clots

On the positive side, they did have a lower risk of colorectal cancer and bone fractures.

Meanwhile, other research has shown a link between combined hormone therapy and an increased risk of dying from non-small cell lung cancer for women who develop the disease.

Because of the risks, doctors typically do not recommend combined hormone therapy. This is especially true for women who have a history of breast cancer or who have a higher risk of breast cancer. In some cases, women receive combined hormone therapy at a low dose for a short time for severe menopausal symptoms.

Doctors consider hormone therapy with estrogen alone only for women who have had a hysterectomy. A hysterectomy is the surgical removal of the uterus. Estrogen that is not balanced by progesterone can spur growth of the uterus lining. That growth increases the risk of uterine cancer.

The effects of combined hormone therapy on women are controversial. Additionally, the risks and benefits of the treatment are different for each woman. Research in this area is ongoing.

If you are considering hormone therapy for menopausal symptoms, talk with your doctor. Share your symptoms and medical history. And ask about options for relieving your symptoms, including the associated risks and benefits.

More Information

Understanding Cancer Risk

Additional Resources

National Institute on Aging: Menopause: Time for a Change

National Cancer Institute: Menopausal Hormone Therapy and Cancer

National Institutes of Health: Menopausal Hormone Therapy Information