Can Progestin Birth Control Actually Increase Your Breast Cancer Risk?

You might have seen headlines recently about a new study, which found that some people who take progestin-only birth control may have higher chances of developing breast cancer. The statements like “progestogen-only pill breast cancer risk revealed” or “all types of hormonal birth control raise breast cancer risk slightly, study finds” may have made you pause.

However, there are a few things you should know before your panic about your contraceptive.

The research, which was published in PLoS Medicine, looked at women under 50 and compared those who had breast cancer with those who did not. The results suggested that taking progestin-based birth control was associated with a nominal increase in risk for the disease.

Progestin, which is a synthetic version of the hormone progesterone, is often used alone in contraceptives like IUDs and hormone injections, as well as some forms of the pill. (People also refer to progestin as progesterone or progestogen.) Previous research has shown that other types of hormonal birth control, which contain both estrogen and progesterone, also carry a slightly increased risk of developing breast cancer.

“The majority of the data we have is for a combination of estrogen and progesterone oral combined contraceptive,” said Dr. Katina Robison, director of gynecologic oncology at Tufts Medical Center in Massachusetts. (Robinson was not affiliated with the study.)

“There’s a big trend to progestin-only contraceptive that we’ve been using. That includes injectables and IUDs, which are incredibly common now. And then pills,” Robison said. “So, they looked at all of those, which is unique in this study.”

The U.K.-based study compared data from 9,498 women under 50 with breast cancer with a control group of 18,171 women who did not have breast cancer from 1996 to 2017. But the results found, while there was an increased risk for women under 50, the percentage is incredibly low, according to Robinson.

The study found that for women ages 16 to 35 who took progestin-only birth control, the risk increased by less than 1%. So, it barely changed, Robison said.

For women 35 to 39, the increase was higher at 20% to 30%. But even that isn’t as scary as it sounds: Since breast cancer is more rare in women under 50, the actual risk may have gone up by 20% to 30% in the study, but that equates to only increased risk from 2% to 2.2% overall. In other words, this should not cause too much alarm, Robinson stressed.

That said, the study does have a few limitations. The patient’s full medical history was not available, so it’s unknown if patients were on other forms of birth control prior to the study or if they had other risk factors like family history or if they smoke. Additionally, the study focused on the short-term risk of developing breast cancer — the long-term risk of using the contraception is unknown.

Additionally, birth control comes with its benefits, too. Many people take birth control so they don’t have to worry about getting pregnant. Birth control can help control period cramps, make periods lighter and can keep cysts from occurring in your breasts and ovaries, according to Planned Parenthood.

Beyond this, Robison said it also can help reduce your risk of some cancers. “These progesterone types of contraceptives are used to treat endometrial cancer and pre-cancers, so there’s also benefits, even cancer-related benefits, that we often don’t talk about when we see these types of studies,” Robison said. Birth control is also known to decrease the risk of ovarian cancer, she added.

If you’re worried about your breast cancer risk, talk to your doctor. While this study does show that there is a slightly increased risk of developing breast cancer, it’s not something to ditch your birth control over.

“I think that this, in my opinion, shouldn’t change any recommendations for using progesterone-only contraception for women. I think it doesn’t change that at all,” Robison said.

If you are worried, your physician can inform you on the steps you can take to mitigate your risk and help you monitor any early signs of the disease. According to Robison, maintaining a healthy diet, limiting your alcohol intake and committing to regular exercise are all ways to help prevent breast cancer.

“Another thing that I think is really important is for women to know there are genetic links to breast cancer,” she added.

If you have a family history of breast cancer or ovarian cancer, it’s important to let your doctor know so they can determine if you’re eligible for testing or early screenings. Being proactive is the best way to reduce your risk ― more so than changing a contraceptive that’s otherwise working for you.