HRT, the Pill, contraception and cancer | World Cancer Research Fund (2024)

Hormone therapies, including hormone replacement therapy (HRT) and hormonal contraceptives such as the combined contraceptive pill (also known as the Pill), play important roles in women’s health. While these treatments offer many benefits, there are also concerns about their potential impact on cancer risk. This page aims to provide the information you need to help you make informed decisions about your health.

What is HRT?

HRT is a treatment used to ease symptoms of the menopause by replacing hormones that naturally decline during this phase of life. It mainly contains oestrogen, often combined with progesterone (known as combined HRT). You can take HRT in various forms, including tablets, skin patches, gels, spray, pessaries or cream.

What is the Pill and other hormonal contraceptives?

Hormonal contraceptives are used for birth control (preventing pregnancy) and managing other health conditions. They come in various forms:

• combined pill (contains oestrogen and progesterone)
• mini-pill (contains progesterone only)
• contraceptive patches (contains oestrogen and progesterone)
• hormonal coil (contains progesterone only)
• hormonal implant (contains progesterone only)
• contraceptive injections (contains progesterone only)

The science behind hormone therapies and cancer

• The increased cancer risks associated with hormone therapies are generally small.
• For many women, the benefits of these hormone treatments are far greater than the risks.

The relationship between hormone therapies and cancer risk is complex and still being studied.

Hormones like oestrogen and progesterone can affect the growth of certain cancer cells – this may explain the slight increased risks. But these hormones also play an important part in keeping us healthy. This is why treatments like HRT can have a number of benefits.

It’s important to note that much of the research on HRT and cancer risk is based on older studies. These studies used different formulations than those commonly prescribed today. Newer hormones that are more similar to our own body may have different health effects, and research is ongoing.

Our conclusion

While hormone therapies like HRT and hormonal contraceptives may slightly increase the risk of certain cancers, these risks are generally small and often outweighed by the benefits for many women. It’s important not to use HRT for more than 5 years.

Discuss your personal situation and medical history with your doctor to make the best decision for your health. For more information and support in the UK, visit the NHS website for HRT and hormonal contraception. Recommendations may vary depending on the country.

Remember, the best way to reduce your overall cancer risk is by eating well, keeping active, keeping a healthy weight, avoiding smoking and keeping safe in the sun.

Sources and references

• HRT and cancer references
  • NHS: Benefits and risks of HRT
  • Breast Cancer Now: HRT and breast cancer risk
  • Cancer Research UK: Does hormone replacement therapy (HRT) increase the risk of cancer?
  • National Institute for Health and Care Excellence (NICE): Long-term benefits and risks of HRT
  • Type and timing of menopausal hormone therapy and breast cancer risk: individual participant meta-analysis of the worldwide epidemiological evidence (2019).
  • Menopausal Hormone Replacement Therapy and the Risk of Ovarian Cancer: A Meta-Analysis (2019).
  • Hormone replacement therapy and the risk of endometrial cancer: A systematic review. (2016).
  • The effect of estrogen vs. combined estrogen-progestogen therapy on the risk of colorectal cancer (2011).
• Hormonal contraceptives and cancer references
  • NHS: Side effects and risks of the combined contraceptive pill
  • NHS: Side effects and risks of the progesterone-only pill
  • Breast Cancer Now: The pill, contraception and breast cancer risk
  • Cancer Research UK: Does the contraceptive pill increase risk of cancer?
  • Combined and progestagen-only hormonal contraceptives and breast cancer risk: A UK nested case–control study and meta-analysis (2023).
  • Oral contraceptives use and risk of cervical cancer – A systematic review & meta-analysis (2020).
  • Endometrial cancer and oral contraceptives: an individual participant meta-analysis of 27 276 women with endometrial cancer from 36 epidemiological studies (2015).
  • Oral contraceptive pills as primary prevention for ovarian cancer: a systematic review and meta-analysis (2013).
  • Oral contraceptives and colorectal cancer risk: a systematic review and meta-analysis (2009).

Explore the evidence and reduce your risk