The potential risks of hormone therapy

Hormone therapy has been used to treat menopause symptoms since the 1940s, and by the 1980s, hormones were also being prescribed to prevent cardiovascular disease and osteoporosis, including in women past menopause age.

In the early 2000s, researchers conducted a large-scale study called the Women's Health Initiative (WHI) to test whether estrogen or progesterone could help prevent chronic diseases in women with and without heart disease. However, the trials were stopped after researchers found that hormone treatments did not reduce heart attacks but instead increased the risk of blood clots, strokes, and breast cancer.

In 2003, a black box warning was added to hormone treatments containing estrogen, saying that they could potentially increase the risk of heart attack, strokes, blood clots, and certain cancers. Practice guidelines also stopped recommending hormones to prevent heart disease, and the use of hormones for menopause symptoms dropped from 27% in the early 2000s to roughly 5% in 2020.

However, major medical societies, including the Menopause Society and the American College of Obstetricians and Gynecologists (ACOG), have for years urged FDA to reevaluate warning labels for certain hormone replacement treatments, such as vaginal estrogen products. These products are low-dose and applied topically, not oral formulations like the treatments tested in the WHI study.

Some researchers have also criticized the findings of the WHI study, arguing it overstated the risks of breast cancer since the participants were mainly older women. The average participant was around 63 years old, while menopause typically occurs in the early 50s.

"We don't start women who are 14 years postmenopausal on hormone therapy. They're started when they're newly menopausal," said Robert Kauffman, an obstetrician-gynecologist and chief of the menopausal service at Texas Tech University HSC School of Medicine. "So the patients in the original study weren't representative of the women we actually treat."

FDA to remove warnings on hormone replacement treatments

On Monday, FDA announced that it would remove warnings from all hormone replacement treatments that contain estrogen. Instead, the labels will be updated with age-specific guidance and outline potential long-term health benefits if patients begin treatment within 10 years of menopause onset.

FDA will work with companies to update their products' labels and remove any references to risks of cardiovascular disease, breast cancer, and probable dementia. However, FDA does not plan to remove a warning for endometrial cancer for systemic estrogen-only products.

In an interview with CBS News, FDA Commissioner Marty Makary said the change would end a decades-long "fear machine" around hormone replacement therapy.

"Removing the black box and putting warnings in a lengthy label that many doctors and most patients will not read is taking women's health backward," said Diana Zuckerman, a scientist and president of the National Center for Health Research.

"The claim that hormones for menopause is the best way to improve the health of women is inconsistent with years of research and will harm millions of women," Zuckerman added. "There are many better ways to reduce the chances of osteoporosis, heart disease, cancer and dementia than hormone therapy for menopause."

"It remains essential that women are fully informed about the overall risks versus benefits," said Jacques Rossouw and Garnet Anderson, the lead authors of the WHI study. Although the researchers have not taken an official position on FDA's decision to remove warnings from hormone treatments, they noted that there have been no large, randomized trials on the treatments since their study. "This information given should be based on the most rigorous science rather than anecdotal evidence," the researchers wrote.