Women who use some hormone-releasing intrauterine devices (IUDs) may have an increased risk for breast cancer, according to a new study published in JAMA Network.

 

The study adds to existing evidence that women who use IUDs—which have become increasingly popular in recent years—have higher rates of breast cancer, though experts have stressed that the overall risk remains low.

 

The study looked at years of data involving nearly 160,000 women in Denmark between ages 15 and 49 years, reports CNN. Half of this group—78,595 women—used levonorgestrel IUDs, known in the United States by the brand names Mirena, Liletta, Kyleena and Skyla, while the other half didn’t use such devices.

 

Levonorgestrel is a synthetic hormone used in birth control methods including IUDs, long-term birth control pills and emergency contraceptives. Levonorgestrel belongs to a class of medications called progestins and works by preventing the release of an egg from the ovary, according to the Mayo Clinic.

 

About 1,600 women out of the total 157,190 analyzed were diagnosed with breast cancer. The risk of developing breast cancer was about 40% higher for women who used IUDs compared with those who did not use the devices, which translates to an estimated 14 more breast cancer cases per 10,000 women over five years. Duration of use of an IUD did not increase risk, noted researchers.

 

In the United States, about 14% of women ages 15 to 49 using contraception take oral contraception pills, and about 10% use long-acting devices. such as IUDs, according to the Centers for Disease Control and Prevention (CDC).

 

“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,” Kelsey Hampton, the director of mission communications and education for the Susan G. Komen Breast Cancer Foundation, who was not involved with the new research, told CNN. “We don’t want people to see this data and feel fear,” she added.

 

Experts encourage women to weigh the pros and cons of starting hormonal birth control. In fact, when earlier research was published about the link between hormonal contraception use and breast cancer risk, the American College of Obstetricians and Gynecologists issued an advisory to help weigh the potential risks against the benefits.

 

In the advisory, experts note that more research is needed to confirm the relationship between progestin-only contraceptives and breast cancer risk. In addition, it notes that hormonal contraception offers other significant health benefits, such as decreased risk for ovarian, endometrial and colon cancer.

 

Discussing the study, Eleanor Bimla Schwarz, MD, MS, professor of medicine at the University of California, San Francisco, pointed out that “the new data shouldn’t change the way women think about the contraception options available to them.” Schwarz added: “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.”

 

To learn more, click #Birth Control or Cancer Health’s Basics on Breast Cancer. It reads in part:

 

Who gets breast cancer?

Breast cancer is the second most common cancer among women, after skin cancer. An estimated 310,700 women are diagnosed with invasive breast cancer annually, according to the American Cancer Society. Men can also develop breast cancer, but this is rare. People with BRCA mutations are at high risk for breast cancer.

 

Around a quarter of women with early breast cancer will go on to develop metastatic disease. About 15% of breast cancer patients have hard-to-treat triple-negative breast cancer, which is more common among young women and Black women.

 

What are the risk factors for breast cancer?

According to the CDC, besides being a woman and getting older, other factors that influence the risk of developing breast cancer include:

 

  • Genetic mutations (including BRCA1 and BRCA2)
  • Family history of breast cancer
  • Early onset of menstruation or early menopause
  • No full-term pregnancies or first pregnancy at an older age
  • Not being physically active
  • Overweight or obesity, especially after menopause
  • Use of oral contraceptives or hormone replacement therapy
  • Previous radiation therapy
  • Drinking alcohol.

 

What are the symptoms of breast cancer?

The most common sign of breast cancer is a lump or mass. A hard and painless mass is most likely to be malignant, but cancerous tumors can sometimes be tender, soft or painful. Other symptoms may include breast swelling, skin irritation or dimpling, breast or nipple pain, nipple retraction (turning inward), redness, scaliness or thickening of the nipples or skin of the breast and discharge from the nipple.