Birth Control Pills and Cancer Risk

Birth control pills (BCPs) are a type of contraception. Contraception is a way to prevent pregnancy. BCPs have hormones in them that prevent you from getting pregnant. BCPs have man-made forms of estrogen and progestin or just progestin. They were first available in the 1960s, but over the years there have been changes to how they are made. Since there have been these changes, older studies that looked at cancer risk can’t be applied to how BCPs are made today. There have been more recent studies that can give some idea about BCPs today and their cancer risks and benefits.

Breast Cancer

Some recent studies have found:

• An increase in breast cancer risk for women who use BCPs (thought to be between a 7 to 30% increase in different studies). The increase in risk is greatest in women over 40 years of age.
• Breast cancer risk is higher when BCPs are used for longer periods of time.
• The risk of breast cancer went down after a woman stopped taking BCPs.
• 10 years after stopping BCPs, there was no increased risk of breast cancer compared to women who had never used BCPs.

Cervical Cancer

Women who take BCPs for 5 years or more have a higher risk of cervical cancer. This risk increases as BCPs are used for longer periods. As with breast cancer, the risk goes back down over time after BCPs are stopped.

Endometrial Cancer

The risk of endometrial cancer is lower among women who have taken BCPs. Some studies put the risk at about 30% lower. That number increases as BCPs are used for longer periods. This lower risk lasted for many years after stopping BCPs.

Ovarian Cancer

The risk of ovarian cancer is about 30 to 50% lower in women who have taken BCPs. The risk keeps decreasing the longer a woman takes BCPs. This lower risk is still seen up to 30 years after stopping BCPs.

Colorectal Cancer

The risk of colorectal cancer is 15 to 20% lower in women who have taken BCPs.

What can I do with all this information?

Talk about the risks and benefits of any medication you are taking with your healthcare provider. It is important for your provider to consider your personal and family history before prescribing BCPs. If you are at an increased risk of cancer, you may consider other options for birth control. These risks include:

• Your family history.
• Genetic mutations.
• Other health concerns (such as blood clots).

Non-hormonal birth control options do not affect your cancer risk. Your provider will talk with you about your options.

If you took BCPs in the past, talk to your provider about cancer screening tests for breast and cervical cancers that are recommended based on your age.

Resources for more information

American Cancer Society: Birth Control & Cancer: Which Methods Raise, Lower Risk

BreastCancer.org: Do Hormonal Contraceptives Increase Breast Cancer Risk?

National Cancer Institute (NCI): Oral Contraceptives and Cancer Risk