What the research shows about birth control and cancer risk

Some forms of birth control do carry a small increase in cancer risk, while others may actually lower it. The relationship depends on which type of birth control you use and which cancer you're asking about. Hormonal birth control—pills, patches, rings, and shots that contain estrogen or progestin—has been studied extensively, and the findings are nuanced rather than a simple yes or no.

The most studied form is the birth control pill. Research shows that people currently using or recently using hormonal pills have a slightly higher risk of breast cancer and cervical cancer than people who have never used them. However, this increased risk is small, and it decreases after you stop taking the pill. For ovarian and endometrial cancer, hormonal birth control actually lowers the risk—sometimes significantly. The longer you use it, the more protection you gain against these cancers, and that protection can last for years after you stop.

Non-hormonal methods like copper IUDs, barrier methods, and fertility awareness do not carry the same cancer risks because they don't use hormones. The hormonal IUD (which releases a small amount of progestin directly into the uterus) appears to carry less risk than pills because the hormone dose is much lower and stays mostly local rather than circulating through your whole body.

Key Takeaways

  • Hormonal birth control slightly increases breast and cervical cancer risk while you use it, but the increase is small and reversible after you stop.
  • The same hormonal methods lower your risk of ovarian and endometrial cancer, sometimes substantially, with protection lasting years after you stop.
  • Your individual risk depends on your age, family history, smoking status, and how long you use hormonal birth control.
  • Non-hormonal methods like copper IUDs do not carry the same cancer risks because they contain no hormones.
  • Discussing your personal cancer risk factors with your doctor helps you weigh the benefits and risks of each birth control option.

How hormonal birth control affects breast cancer risk

Hormonal birth control increases breast cancer risk by a small amount while you are actively using it. Studies show the increase is roughly 20 to 30 percent higher than the baseline risk for women not using hormonal methods—but this is an increase in relative risk, not absolute risk. In practical terms, if your baseline risk of breast cancer by age 50 is 2 percent, a 20 percent increase means your risk becomes about 2.4 percent.

The increased risk appears to be related to the estrogen in the pill. It is highest in the first few years of use and decreases over time. Once you stop taking hormonal birth control, your breast cancer risk returns to baseline within about five years. This means the risk is temporary and tied directly to when you are using the method.

Your personal risk factors matter significantly. If you have a family history of breast cancer, are over 35, or smoke, your baseline risk is already higher, and adding hormonal birth control increases it further. Conversely, if you have no family history and are younger, your baseline risk is lower to begin with, so the absolute increase is smaller.

Cervical cancer risk and hormonal birth control

Hormonal birth control is associated with a modest increase in cervical cancer risk, particularly with longer use. The increase appears to be related to how the hormones affect the cervix and possibly to changes in sexual behavior or partner exposure to human papillomavirus (HPV), the virus that causes most cervical cancers. Like breast cancer risk, cervical cancer risk decreases after you stop using hormonal methods.

The HPV vaccine (Gardasil or Cervarix) protects against the viruses most likely to cause cervical cancer. If you received the vaccine before starting hormonal birth control, your cervical cancer risk is substantially lower than it would be otherwise. Regular cervical cancer screening (Pap tests or HPV tests) also catches precancerous changes early, when they are highly treatable.

The increased cervical cancer risk from hormonal birth control is real but remains small in absolute terms. Your screening status and vaccination history matter more to your actual risk than the birth control method you choose.

Why hormonal birth control lowers ovarian and endometrial cancer risk

Hormonal birth control significantly reduces the risk of ovarian cancer and endometrial cancer (cancer of the uterine lining). The protection comes from suppressing ovulation—when you don't ovulate, the cells lining your ovaries and uterus don't go through the repeated growth and division that can lead to cancer. The longer you use hormonal birth control, the greater the protection, and this protection persists for years after you stop.

For ovarian cancer, the risk reduction is substantial: people who use hormonal birth control for five years or longer have roughly half the risk of ovarian cancer compared to people who never use it. For endometrial cancer, the reduction is similar. These cancers are less common than breast cancer, so the absolute number of cases prevented is smaller, but the percentage reduction is significant.

This protective effect is one reason some doctors recommend hormonal birth control for people at high risk of ovarian or endometrial cancer due to family history or genetic factors like BRCA mutations. The decision to use birth control for cancer prevention is personal and should involve discussion with your doctor about your specific risk factors.

Other cancer types and birth control

Research on hormonal birth control and other cancers is less extensive, but current evidence suggests no increased risk for colorectal cancer, melanoma, or non-Hodgkin lymphoma. Some older studies raised concerns about liver cancer, but modern hormonal birth control uses much lower hormone doses, and current evidence does not support an increased risk.

The type of progestin in your birth control may matter for some cancers. Older formulations used different progestins than modern pills, and some research suggests certain progestins carry different risks. If you have concerns about a specific formulation, your doctor can discuss which options may be better suited to your health history.

How your age and health history change the picture

Your age significantly affects how you should think about birth control and cancer risk. Younger people have a much lower baseline cancer risk overall, so the small percentage increase from hormonal birth control translates to a very small absolute increase. A 20-year-old using the pill faces a different risk calculation than a 45-year-old, even though the percentage increase is the same.

Your family history of cancer, personal history of blood clots, smoking status, and whether you have had the HPV vaccine all shape your individual risk profile. Someone with a strong family history of breast cancer may reasonably choose a non-hormonal method, while someone with a family history of ovarian cancer might choose hormonal birth control specifically for its protective effect. These are conversations to have with your doctor, not decisions to make based on general information alone.

If you have had cancer in the past, hormonal birth control may or may not be safe for you, depending on the cancer type and your treatment. Some cancers are hormone-sensitive, meaning they grow faster in the presence of estrogen or progestin. Your oncologist and gynecologist should coordinate on this decision.

Non-hormonal birth control options

If you want to avoid hormonal methods entirely, several effective options exist. Copper IUDs (like Paragard) prevent pregnancy by creating an inflammatory response that is toxic to sperm. They do not use hormones and do not carry the same cancer risks as hormonal methods. They are highly effective, last 10 years, and can be removed at any time.

Barrier methods—condoms, diaphragms, and cervical caps—prevent sperm from reaching the egg. They have no systemic hormonal effects and no cancer risk. They are less effective than IUDs or hormonal methods if used inconsistently, but they also protect against sexually transmitted infections.

Fertility awareness methods involve tracking ovulation and avoiding sex during fertile days. They require consistent tracking and motivation but carry no health risks. Permanent methods like tubal ligation or vasectomy are highly effective for people certain they do not want children.

Frequently Asked Questions

Does the birth control pill cause cancer?

Hormonal pills slightly increase breast and cervical cancer risk while you use them, but the increase is small and reversible. They also lower ovarian and endometrial cancer risk substantially. The overall cancer risk depends on which cancers you're asking about and your personal risk factors.

Is the hormonal IUD safer than the pill?

The hormonal IUD releases a much smaller dose of progestin directly into the uterus rather than circulating it through your whole body. This may mean lower cancer risk compared to pills, though research is still ongoing. The copper IUD has no hormones at all and no associated cancer risk.

If I stop taking birth control, does my cancer risk go back to normal?

Yes. Breast and cervical cancer risk return to baseline within about five years of stopping hormonal birth control. The protective effect against ovarian and endometrial cancer persists for years after you stop, which is one reason the long-term benefit can outweigh short-term risks.

Should I get the HPV vaccine if I use hormonal birth control?

Yes. The HPV vaccine protects against the viruses that cause most cervical cancers and is recommended for people up to age 45. It substantially reduces your cervical cancer risk regardless of which birth control method you use.

What should I discuss with my doctor about birth control and cancer risk?

Tell your doctor about any family history of cancer, your age, whether you smoke, and any previous blood clots or cancer diagnosis. Ask which birth control methods carry the most and least risk for your specific situation, and discuss whether the benefits of hormonal birth control outweigh the risks in your case.