Overall cancer risk
Overall, if there is an increase
in cancer risks for women taking hormonal birth control, it appears to be very
small. Taking the Pill may reduce a woman's risk for most cancers. This benefit
for some cancers may last as long as 15 years after a woman stops taking the
Pill. However, long-term use of the Pill (more than 8 years) may slightly
increase a woman's overall risk of cancer.1
Breast cancer risk
Based on the
following findings, experts say that estrogen-progestin contraception pills
have little, if any, effect on
breast cancer.2
Some experts say that birth control hormones DO NOT 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.3 (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.4
- 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.3
Some experts say that 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.5
- 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.3
Cervical cancer risk
Cervical cancer
is caused by infection with a sexually transmitted
human papillomavirus (HPV).
The
Gardasil
vaccine
(What is a PDF document?), for girls or women ages 9 to 26, protects against the most
common forms of genital warts that cause cervical cancer.6 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.5
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.7
Colon cancer and endometrial cancer protection
Taking combination birth control pills for 1 year or longer lowers the
risk of colon cancer and cancer of the uterine lining (endometrial
cancer). The longer you take the Pill, the lower your risk of
endometrial cancer.2