Study: Some IUDs may increase breast cancer risks

A recent study has found that women who use hormonal birth control, particularly intrauterine devices (IUDs), have higher rates of breast cancer — although experts stressed that the overall risk remains low.

Hormonal IUDs work by delivering small amounts of hormones directly into the uterus.

Previous studies showed they provided a lower breast cancer risk than hormonal pills because they delivered smaller amounts of hormones into the uterus.

But the new study, published on Wednesday in Journal JAMA Network, discovered that women who use levonorgestrel-releasing IUDs face an increased risk of breast cancer, an unexpected finding given that IUDs were thought to be lower risk.

In the study of 150,000 Danish women between the ages of 15 to 49 evenly split, researchers looked into those who used levonorgestrel-releasing IUDs and compared them with those who did not use the devices.

Amont the women, there were about 1,600 new breast cancer diagnoses overall. But there was a 40% higher risk among women who used IUDs. This translates to an estimated 14 more breast cancer cases per 10,000 women over five years.

The researchers also found that the duration of IUD use did not increase the risk of cancer and IUD overall risk remains low.

Kelsey Hampton, director of mission communications for the Susan G. Komen Breast Cancer Foundation, urged people to use the study to make informed conversations and decisions.

“It’s normal for people to see studies like this and feel panicked or worried because an increase in risk of developing any kind of cancer is worrisome,” she said.

“We don’t want people to see this data and feel fear. We want them to know that this is just more evidence and more information that they can use to have an educated conversation with their doctor.”

However, on her part, Eleanor Bimla Schwarz, professor of medicine at the University of California, criticised the study, saying it reported just a small fraction and it should not change women’s mentality about contraception options.

She said that the benefits of an IUD far outweigh the risks.

Schwartz further said hormonal IUDs can help reduce bleeding and cramping and may decrease a woman’s risk of endometrial cancer.

“It reports a very small, one-in-a-thousand risk of being diagnosed with breast cancer, which is not the same as dying of breast cancer,” she said.

“That risk is really lower than many other everyday risks that women frequently take that have an impact on their breast cancer risk.

“I really think we have to put these conversations in context. A breast cancer diagnosis is not the same as dying from breast cancer, and we don’t have studies that show the use of any form of hormonal contraception actually increases your risk of dying from breast cancer.”

Arif Kamal, the chief patient officer with the American Cancer Society, also advised women to consider other contraceptive options if they are worried about the risk of IUDs.

“There’s not a one-size-fits-all approach. A person’s risk of breast cancer and their underlying anxiety or worry about breast cancer should inform a decision that’s made between a woman and her doctor about what’s the right thing to do,” Kammal said.