Ovarian cancer is cancer in your ovaries, female reproductive glands that produce eggs and hormones. In the U.S., it causes more deaths each year than any other cancer that affects women's reproductive systems.
Lots of things influence your risk for ovarian cancer, including your age, overall health, and family history. But certain types of birth control can lower your risk.
One of the most common types of birth control is "the pill." Most pills are combination pills, lab-made combinations of hormones that mimic those made by a woman’s own body. These hormones, estrogen and progesterone, work to stop your ovaries from releasing eggs and keep sperm from reaching your eggs.
Your risk of ovarian cancer starts to go down once you take the combination pill for as little as 3 to 6 months. It continues to go down the longer you take it. That's true even if you have changes, or mutations, in certain genes (BRCA1 or BRCA2) that can raise your risk of ovarian cancer.
Overall, the pill lowers your risk of getting ovarian cancer by 30% to 50%. This effect can last for up to 30 years after you stop taking it.
Other Hormonal Birth Control
Like the pill, other types of birth control also deliver synthetic hormones. These include the vaginal ring, which you place inside your vagina, and the birth control patch, which goes on your skin. Each slowly delivers estrogen and progestin to prevent pregnancy. You replace the patch weekly (except for the week you're on your period), and the ring every 3 weeks.
These are newer products, so we don't have as many studies on them. But scientists think they protect against ovarian cancer in the same way as the pill.
DMPA (Depo-Provera) is a shot you can get to prevent pregnancy. Sometimes called "the shot," its main ingredient is depo medroxyprogesterone, a man-made form of progesterone. Your doctor injects it into your upper arm or buttock every 3 months. The shot also lowers your risk of ovarian cancer, especially if you use it for more than 3 years.
Another common type of birth control is an intrauterine device (IUD). It's a small metal or plastic object that your doctor places in your uterus.
Certain types of IUDs, called hormonal IUDs, release the hormone progestin (a type of progesterone). This thickens the mucus around your cervix and thins the lining of your uterus. That slows sperm down to keep you from getting pregnant. Others are made of copper, which triggers an immune response in your uterus that prevents pregnancy.
One large study found that overall, women who use IUDs may lower their risk of ovarian cancer by up to 32%,
Surgery for Birth Control
Certain surgeries that prevent pregnancy might also lessen your risk for ovarian cancer.
In tubal ligation, a surgeon ties off your fallopian tubes, which carry eggs from your ovaries to your uterus. This surgery, sometimes called having your tubes tied, is thought to reduce your risk of ovarian cancer by about 25%.
Salpingectomy, the removal of your fallopian tubes, reduces your risk even more than tubal ligation. We need more research, but some studies show it may cut your odds by anywhere from 42% to 77%.
A type of hysterectomy in which doctors remove your uterus, but not necessarily your ovaries or fallopian tubes, reduces your risk by about 30%.
There are lots of things to consider when you pick your birth control method. For example, hormonal birth control methods like the pill not only lower your risk for ovarian cancer, but for endometrial cancer, too.
On the other hand, hormonal birth control methods can raise your risk of cervical and breast cancers. But the increase is very small, especially if you're younger than your mid-40s. That's when you’re most likely to take the pill anyway.
Your health, lifestyle, genes, and medications you take all play a part in how birth control affects your cancer risk. So talk to your doctor about the best method for you.