From the Guidelines
Intrauterine devices (IUDs) do not increase the overall risk of cancer and may actually provide protective effects against certain types of cancer, such as endometrial and ovarian cancer, as supported by recent studies 1.
Key Points
- Both hormonal and copper IUDs have been associated with a reduced risk of endometrial cancer, with studies showing up to a 30-40% reduction in risk.
- Hormonal IUDs containing levonorgestrel work by thinning the uterine lining, which may explain this protective effect.
- For ovarian cancer, both types of IUDs appear to offer some protection, potentially reducing risk by 15-30%.
- Regarding cervical cancer, the evidence is mixed, but more recent research indicates no significant association when accounting for other risk factors like HPV infection 1.
- For breast cancer, current evidence suggests no increased risk with IUD use, and the copper IUD contains no hormones, while hormonal IUDs release lower levels of hormones that act primarily locally in the uterus rather than systemically 1.
Considerations
- If you have a personal or family history of cancer, discuss your specific situation with your healthcare provider to determine the most appropriate contraceptive option for you.
- The use of IUDs is considered safe for most women, including those with a history of cancer, but certain conditions, such as active cancer or recent cancer treatment, may require special consideration 1.
- The Society of Family Planning guidelines recommend the use of IUDs or implantable contraceptives for most women who are receiving treatment for cancer, and the use of any method of contraception is recommended for women who have been free of cancer for at least 6 months and have no history of hormonally mediated cancers 1.
From the Research
IUD and Risk of Cancer
- The relationship between IUD use and cancer risk has been studied in various types of cancer, including breast, endometrial, cervical, and ovarian cancer.
- A study published in 2011 2 found no increased risk of breast cancer for users of levonorgestrel-releasing intrauterine devices (LNG-IUD) compared to copper IUDs.
- However, a systematic review and meta-analysis published in 2020 3 found an increased breast cancer risk in LNG-IUS users, with an odds ratio of 1.16 (95% CI 1.06-1.28).
- In contrast, a study published in 2023 4 found that both levonorgestrel-releasing and copper IUDs reduce the risk of endometrial cancer, and that the evidence for a protective effect of IUD use against ovarian cancer is less consistent.
- Another study published in 2017 5 found that women who used an IUD experienced less cervical cancer, with a summary odds ratio of 0.64 (95% CI 0.53-0.77).
- A systematic review and meta-analysis published in 2021 6 found that ever-use of an IUD reduces the risk of ovarian cancer by an average of 30%, with an estimated OR of 0.67 (95% CI 0.60-0.74).
Types of Cancer
- Breast Cancer: The evidence for a relationship between IUD use and breast cancer risk is mixed, with some studies finding no increased risk 2 and others finding an increased risk 3.
- Endometrial Cancer: Both levonorgestrel-releasing and copper IUDs have been found to reduce the risk of endometrial cancer 4.
- Cervical Cancer: IUD use has been found to reduce the risk of cervical cancer, with a summary odds ratio of 0.64 (95% CI 0.53-0.77) 5.
- Ovarian Cancer: Ever-use of an IUD has been found to reduce the risk of ovarian cancer by an average of 30%, with an estimated OR of 0.67 (95% CI 0.60-0.74) 6.