Hormone replacement therapy (HRT) is a treatment option for menopause-related symptoms. Although it can increase the chance of breast cancer, this risk is small and will return to average after a person stops HRT. A person should discuss the benefits and risks of HRT with a healthcare professional.
The risk of breast cancer can dramatically decrease after a person discontinues using HRT. However, the amount of time this takes is not definitive.
The breast cancer risk also depends on the type of HRT a person is taking.
The following article discusses how much HRT increases the risk of breast cancer, ways to prevent breast cancer, and potential alternatives to HRT.
BreastCancer.org notes that the number of people using HRT has dropped since research from 2002 initially found a link between HRT and breast cancer.
The researchers noted that prolonged or long-term use of either combined progesterone and estrogen or estrogen-only therapies significantly increased the risk of breast cancer.
They found that the level of risk can differ between the types of HRT.
They also stated that HRT using estradiol-dydrogesterone had the lowest risk for breast cancer development and that the risk appeared to drop after the use of HRT stopped.
Breast Cancer Now, a British charity, notes that the risk of developing breast cancer if a person is aged between 50–96 is as follows:
- 63 in 1,000 women who have never taken HRT
- 83 in 1,000 women who use combined HRT for 5 years
- 68 in 1,000 women who use estrogen-only HRT for 5 years
Combined estrogen and progesterone may have the highest risk factor of any type of HRT. According to BreastCancer.org, the risk of developing breast cancer increases by 75% for those taking combined HRT.
The organization also noted that combined HRT increases the chance that a healthcare professional may diagnose a person’s breast cancer at a more advanced stage, which increases the likelihood of mortality.
According to the
The American Cancer Society (ACS) states that the risk of breast cancer returns to average 3 years after a person discontinues combined HRT.
However, the researchers for the 2020 study found that risk reduced after 5 years for medroxyprogesterone, and 10 years for levonorgestrel, which are types of progesterone.
Combined HRT is also linked to breast density, which can make it harder to locate cancer on a mammogram. Breast density is a term to describe the amount of dense tissue compared to fatty tissue in a person’s breast. Dense tissue is more fibrous than fatty tissue.
HRT containing estrogen alone can also increase the risk of a person developing breast cancer. However, it may only increase the risk after 10 years of continued use.
A person who has had or has breast cancer should not take HRT. Instead, they should speak with a doctor about alternative options.
According to the ACS, using HRT following breast cancer can increase the likelihood of recurrence or new tumors developing.
The American College of Obstetricians and Gynecologists notes that the first-line choices for managing menopausal symptoms in people during or after their treatment for breast cancer include nonhormonal approaches.
These include moisturizers, topical anesthetics, and lubricants to treat vaginal symptoms.
Those who have a history of estrogen-dependent breast cancer can use vaginal estrogen therapy if they do not respond to nonhormonal approaches. Vaginal estrogen therapy delivers low doses of hormone.
A 2019 article in the journal Archives of Breast Cancer states that there are no guidelines on the safety of HRT use in those with a family history of breast cancer.
A systematic review from 2021 notes that HRT does not have a relevant effect on the risk of cancer in those who carry the BRCA gene.
Breast Cancer Now suggests that a person should speak with a doctor before using HRT if they have inherited a breast cancer gene, such as BRCA1 or BRCA2.
If a person decides to take HRT, they can ask for a lower-dose formula. They can also discuss with a doctor how to take it for the shortest possible time.
BreastCancer.org notes that a person can take certain steps to reduce their risk of developing breast cancer whether they use HRT or not.
They recommend that a person:
- exercise regularly
- eat nutrient-rich foods
- quit smoking, if applicable
- limit their intake of alcohol
It is also important to achieve and maintain a healthy weight. This is because having more fat tissue can raise a person’s estrogen levels, and as a result, increase the chance of developing breast cancer.
The ACS adds that a person at higher risk for breast cancer may benefit from taking additional steps, such as:
- getting closer monitoring
- seeking genetic testing and counseling
- getting preventative surgery
For those with a high risk of developing breast cancer, an oncologist may prescribe medications such as tamoxifen and raloxifene.
The benefits of taking HRT can vary from person to person. Some people decide that the benefits outweigh the risks.
A person should discuss the benefits and risks with a healthcare professional before deciding whether HRT is right for them.
If a person decides to take HRT, they should attend all their breast cancer screening appointments.
Some companies produce bioidentical hormone therapy. Bioidentical hormones are theoretically derived from plants.
Many companies claim that their bioidentical hormone products are a safer alternative to conventional HRT, which can consist of synthetic hormones. However, the Food and Drug Administration (FDA) does not regulate these supplements.
Additionally, the higher breast cancer risk is the same for bioidentical hormones as it is for synthetic hormones. Synthetic hormones are made in a laboratory that are chemically identical to those in the body.
A person should speak with a doctor about the risks of HRT, particularly if they have a higher risk of developing breast cancer already. Their doctor will likely suggest a different treatment plan that does not involve HRT.
According to the Office on Women’s Health, a person may not need formal treatment for their menopause symptoms. When they do, some treatments that do not involve HRT can include:
- over-the-counter (OTC) or prescription products to treat vaginal dryness or discomfort, such as vaginal lubricants
- natural remedies, such as soy or red clover
- mind and body practices, such as yoga or acupuncture
Exercise can help improve mood and sleep, and reduce hot flashes. A person should also avoid spicy foods, caffeine, and alcohol, as these can cause hot flashes.
A person can also take the following medications:
- Clonidine: This is a medicine that treats high blood pressure. It may be able to reduce hot flashes and night sweats. However, it can cause side effects including low blood pressure, dry mouth, depression, constipation, and drowsiness. A person can take this medicine for 2–4 weeks to see if it is effective. If it is not, a person should stop taking it.
- Antidepressants: Examples include venlafaxine and citalopram. These may be able to treat hot flashes. Side effects can include nausea, dizziness, sleeping difficulties, and anxiety. They may also cause or low libido and weight gain.
- Tibolone: Tibolone is similar to combined HRT. This is a synthetic hormone that those with a womb can take. However, it contains both estrogen and progesterone, so if a person is unable to take HRT as a result of medical conditions, then they will not be allowed to take this medication.
HRT causes an increased risk of breast cancer. The risk tends to increase with combined therapies as well as long-term use.
A person who has had breast cancer or who has a family history of the disease should speak with a doctor before using HRT for their menopause symptoms. A doctor can discuss other solutions that can include OTC and prescription medications, as well as natural and holistic therapies.