Chemotherapy is a powerful and effective drug used to stop fast-growing cancer cells in the body, but unfortunately, it also carries side effects, including chemo-induced early menopause.
In menopause, periods stop coming. The ovaries stop releasing eggs and (for the most part) producing estrogen. For most women, menopause happens during one’s forties or early fifties as part of the natural aging process, but amenorrhea (the absence of a period) can also occur as a side effect of chemotherapy.
Early menopause can happen to women undergoing chemo for any type of cancer, and the most common type of cancer in people under 50 is breast cancer. It’s estimated that about 1 in 5 women are younger than 50 at the time of their breast cancer diagnosis.
So, what happens to your menstrual cycle during chemotherapy, and how does it affect your overall reproductive health? Keep reading to find out what you need to know about early menopause due to chemo as you navigate the journey through cancer treatment.
Can Chemotherapy Drugs Stop My Period?
Yes. “Chemotherapy often shuts down the ovaries, and it stops the maturation of the eggs that are sitting in the ovaries,” says Mary Jane Minkin, MD, the codirector of the sexuality, intimacy, and menopause program at Smilow Cancer Hospital at the Yale School of Medicine in New Haven, Connecticut.
That’s because chemotherapy is a systemic therapy that targets the entire body, meaning that it’s not only toxic to the cancer cells. It has effects throughout the body, including the ovaries, says Hannah Linden, MD, a professor and oncologist at the Fred Hutch Cancer Center at UW Medicine in Seattle. “That can result in temporary or permanent menopause,” says Dr. Linden.
When Your Period Stops Due to Chemo, How Long Does That Have to Go On for It to Be Considered ‘Menopause’?
Usually, it’s considered menopause when menstruation stops for a year, but it can be later, up to two or three years, says Linden. “There are some blood tests which can give us hints that the ovaries are still active,” she says.
Temporary menopause is when the period stops for less than a year, says Linden.
Will My Periods Eventually Come Back After Chemotherapy?
Sometimes. A major factor in whether a woman’s ovaries “wake up” and resume having periods is age, says Dr. Minken. “If a woman is older, her ovaries are less likely to ‘wake up.’”
Women who are under 40 years old are more likely to experience the return of their periods than women over 40, and women between 40 and 45 years old are more likely to resume their periods than women 45 and older, says Linden.
In a study published in JAMA Network Open in November 2023, among more than 700 premenopausal women who underwent chemo for breast cancer, about half included in a quality of life analysis eventually resumed their periods.
The distribution of women who began menstruating again was as follows:
- 88.6 percent of women between 18 to 34 years old
- 75.2 percent of women between 35 and 39 years old
- 36.4 percent of women between 40 and 44 years old
- 17 percent of women aged 45 and older
For the women who recovered their periods, about 14 percent did so within one year after diagnosis, 21 percent between year 1 and year 2, and 16 percent between year 2 and year 4.
In women who do have their period return, menopause may begin at an earlier age than for other women, according to Susan G. Komen, a nonprofit breast cancer advocacy group.
Are There Any Other Factors That Would Make Permanent Early Menopause More Likely?
Besides age, the type of chemo used may play a role, according to a presentation at ESMO Congress 2022. Anthracycline and taxane-based combination chemotherapy were associated with higher rates of chemo-caused menopause, and treatments with trastuzumab alone and with anthracycline alone were associated with a lower risk of amenorrhea.
Family history is relevant in helping to make these predictions, says Minken. “If a woman has a family history of early menopause, she herself is likelier to be a candidate for earlier menopause. So she may not have great ovarian reserve, but this is not an absolute predictor,” she says.
“Smokers tend to go through menopause a year or two earlier than nonsmokers, so if she is a smoker, it’s a lower chance of her ovaries ‘waking up,’” says Minkin.
Can Chemo-Related Menopause Cause the Same Symptoms Associated With Actual Menopause, Like Hot Flashes and Night Sweats?
When chemo shuts down the ovaries, the production of estrogen stops — basically what happens with menopause. With this cessation of estrogen production, women can experience things like hot flashes, night sweats, and vaginal dryness, all symptoms that happen with menopause, says Minkin.
Because the onset of chemo-related menopause is so sudden, the symptoms may be worse than with natural menopause, according to Susan G. Komen.
“Sometimes when these symptoms stop, it’s because the ovaries are back to producing low levels of hormones,” says Linden.
Are There Treatments That Can Help These Menopause Symptoms?
“Yes — the good news is that we have some wonderful medications that can safely be used by breast cancer patients to take care of hot flashes, sleep issues, and vaginal dryness,” says Minkin.
These treatments can include hormone therapy, vaginal estrogen, certain antidepressants, and vaginal lubricants or moisturizers, according to MedlinePlus.
If I Want to Get Pregnant in the Future, Should I Freeze My Eggs Before I Undergo Chemotherapy?
While there are factors that make it more or less likely that the ovaries may eventually wake up, it’s hard to predict exactly what will happen in each individual woman, says Minkin. “So often we will try to retrieve eggs from young women who want to conceive before they get chemotherapy. Then we can freeze them, and hopefully the woman will be able to conceive once she’s finished with her cancer therapies,” she says.