Breast cancer risk
Based on the following findings, experts say that
estrogen-progestin contraception pills have little, if any, effect on
breast cancer.1
"Birth control hormones do not cause breast
cancer."
- Based on the largest studies of breast cancer
risk, researchers state that women who have a strong family history of breast
cancer can take birth control pills without further raising their breast cancer
risk.2 (Some experts disagree; see below.)
- A recent study of low-dose birth control pills found
no increase in breast cancer cases among current users
and a lower risk of breast cancer among past
users.3
- By the age of 55, past users of
birth control pills have the same rate of breast cancer
diagnosis as women who have never used birth control hormones.2
"Birth control hormones may cause breast
cancer."
- Some experts are not yet convinced that birth
control pills are completely safe for women who have a strong family history of
breast cancer or for women who have the high-risk BRCA1 or BRCA2 gene
mutations.4
- Several past studies have
found a slightly higher-than-normal rate of breast cancer among current users.
This may be because taking birth control hormones promotes the growth of breast
cancer cells that are already present, but would not yet be multiplying on
their own. On the other hand, it may be that these women were closely studied
and breast cancer detection was better than in the normal population.2
Cervical cancer risk
Cervical cancer is caused by infection with a sexually
transmitted
human papillomavirus (HPV). You can lower
your chance of infection by using condoms.
Regular
Pap tests are the most effective screening method for
cervical cancer. Widespread use of the Pap test has greatly lowered rates of
cervical cancer. This is because the test detects precancerous cell changes in
the cervix, before actual cancer starts.
Based on current research, you may be more likely to develop
cervical cancer if you use birth control pills and you are HPV-infected. You
may also be more likely to become infected if you are exposed to HPV. This may
be because long-term use of birth control pills makes the cells of the cervix
more vulnerable.4
Ovarian cancer protection
Combination pills reduce the risk of ovarian cancer after 1 year of
use. This benefit seems to last for years after stopping the Pill.5
Endometrial cancer protection
Taking combination birth control pills for 1 year or longer lowers
the risk of cancer of the uterine lining (endometrial
cancer). The longer you take the Pill, the lower your risk of
endometrial cancer.1