Birth control pills

What you may have heard

People who take birth control pills have an increased risk of cancer.

What science tells us

Birth control pills are used to prevent pregnancy and contain two hormones: estrogen and progesterone that help regulate the menstrual cycle (Cleveland Clinic). Birth control pills prevent pregnancy by stopping ovulation and preventing sperm from penetrating through the cervix. The most commonly prescribed type of oral contraceptive (often referred to as simply “the pill” or sometimes “birth control”) in the United States.

Epidemiological Evidence

The evidence about birth control pills and cancer is mixed, depending on the type of cancer: Oral contraceptives slightly increase risk of breast and cervical cancer, yet decrease risk of endometrial, ovarian, and colorectal cancers.

• Breast: Women who have ever used oral contraceptives have a slight (7%) increase compared with women who had never used oral contraceptives. Women who are currently using oral contraceptives have a 24% increase in risk. Risk of breast cancer also increases the longer oral contraceptives are used (NCI).
• Cervical: Women who have used oral contraceptives for 5 or more years have a higher risk of cervical cancer than women who have never used birth control pills. The longer a woman uses oral contraceptives, the higher the risk of cervical cancer(NCI).
• Endometrial (Uterine): Women who have ever used oral contraceptives have 30% reduced risk of endometrial cancer(NCI). This protective effect continues for many years after the woman stops using oral contraceptives.
• Ovarian: Use of oral contraceptives provide a 30-50% lower risk of ovarian cancer than women who have never used oral contraceptives (NCI). This protection increases with the length of time oral contraceptives are used.
• Colorectal: Oral contraceptives decrease risk of colorectal cancer by 15% to 20% (NCI).

Laboratory Evidence/Supporting Evidence

Hormone exposures in laboratory and animal studies have effects on cells and tissues that are generally consistent with the epidemiological evidence.

IARC Carcinogen Classification: Group 1 (Carcinogenic to Humans)

How to reduce your risk

Talk to your doctor about all contraceptive options and potential risks before making a decision. Your age, weight, reproductive history, and family history may put you at risk for some gynecological cancers. Birth control pills may put women at increased risk for other health problems, such as blood clots, heart disease, and stroke (MD Anderson).

There are bigger cancer risk factors than oral contraceptives. For example, more cases of cervical cancer are caused by the human papillomavirus (HPV) than taking the pill, and more cases of breast cancer are caused by poor diet and low levels of physical activity than oral contraceptives (MD Anderson).

Finally, there are many other contraceptive options that do not affect cancer risk. For example, non-hormonal intrauterine devices (IUDs) are small metal or plastic devices that are placed in the uterus by a gynecologist to prevent pregnancy (MSK).

Bottom line

Oral contraceptives slightly increase risk of breast and cervical cancer, yet decrease risk of endometrial, ovarian, and colorectal cancers. Talk to your doctor to find the best contraception for you.

Learn More From These Trusted Sources

National Cancer Institute (NCI): Oral contraceptives
MD Anderson: Cancer and the pill
Memorial Sloan Kettering (MSK): Birth control and cancer risk

Date

Published: June 29, 2021
Verified/updated: August 22, 2022