Studies show that current or recent use of birth control pills (oral contraceptives) slightly increases the risk of breast cancer [186-189].
A pooled analysis of data from more than 50 studies found that while women were taking birth control pills (and shortly thereafter), they had a 10 to 30 percent higher risk of breast cancer than women who had never used the pill [186]. Once women stopped taking the pill, their risk began to decrease and returned to that of never users in about 10 years [186].
In most studies on this topic, women were taking older, higher-dose forms of the pill.
Weighing the pros and cons of birth control pill use
Although taking the pill slightly increases risk, most women on the pill are at low risk of breast cancer because they are young and premenopausal. So, even with a slight increase in risk, they are still unlikely to get breast cancer. And, once women stop taking the pill, the slight increase in risk begins to decrease and over time, goes away [186].
Before making any decisions about birth control pills, you should weigh the pros and cons of using them. Though they have some risks, birth control pills also have some benefits including preventing unwanted pregnancies and decreasing the risk of both uterine and ovarian cancers [190-191].
Newer birth control pills
One area still under study is how today's lower-dose pills affect breast cancer risk. One large case-control study found no link between these birth control pills and breast cancer [192]. However, more research is needed to draw conclusions.
Some types of birth control pills lower the number of periods a woman has during a year. Others contain progestin, but no estrogen (often called “mini-pills”). At this time, there are too few data to comment on whether these pills affect breast cancer risk the same as other types of birth control pills.
Depo Provera, the birth control patch and the vaginal ring
Like birth control pills, Depo Provera (an injected contraceptive) and the birth control patch contain hormones. Depo Provera contains progestin alone, while the birth control patch and the vaginal ring contain both estrogen and progestin. At this time, data on the potential link between these products and breast cancer risk are limited [193-196].
A pooled analysis and a recent study on Depo Provera showed no impact on breast cancer risk overall. A possible increase in risk was found among current, longer-term users compared to never users [195-196].
Talk to your health care provider about the pros and cons of Depo Provera or other types of birth control containing hormones before using them.
Updated 10/22/12
