February 27, 2024

In the United States, experts recommend regular mammograms starting at age 40

Health experts have released a review of the standard medical advice on mammograms because of the increase in breast cancer diagnoses among young women and the continued high death rates, especially among black women.

According to the United States Preventive Services Task Force, women of all racial and ethnic backgrounds with an average risk of breast cancer should start getting regular mammograms at age 40, rather than waiting until age 50, as previously recommended by the World Health Organization (WHO). )

The group publishes influential guidelines on preventive health, and its recommendations are generally widely accepted in the United States. But the new advice, released as a draft, suggests the opposite.

In 2009, the task force raised the age for starting routine mammograms from 40 to 50. At the time, researchers worried that early screening could do more harm than good, leading to unnecessary treatments in young women whose biopsies turned negative.


The change in recommendation comes after some worrying trends in breast cancer in recent years. Experts cite an apparent increase in the number of cancers diagnosed in women under 50 and a failure to close the survival gap in young black women who die from breast cancer twice as often as white women of the same age.

“We don’t know why there is an increase in breast cancer among women under 40,” said Carol Mangione, immediate past chair of the task force. “But when more people in a given age group get a condition, screening that group can be more impactful.”

The new recommendation covers more than 20 million women between the ages of 40 and 49 in the United States. In 2019, about 60% of women in this age group said they had had a mammogram in the past two years, compared with 76% of women aged 50 to 64 and 78% of women aged 65 to 74.

The panel said there was insufficient evidence to make recommendations one way or the other for women age 75 and older.

Carroll said the task force specifically commissioned breast cancer studies among black women for the first time, as well as all women, and that more research is needed on factors that drive racial disparities. They call for a clinical trial to compare the effectiveness of annual and biennial screening among black women.


Overall, breast cancer mortality has decreased in recent years. Nevertheless, it remains the second most common cancer in women after skin cancer and the second leading cause of cancer deaths among women in the United States after lung cancer.

Between 2000 and 2015, breast cancer diagnoses among women under the age of 40 increased by less than 1%. But the rate increased by an average of 2% per year between 2015 and 2019, the task force noted.

The reasons are not entirely clear. Delaying pregnancy or choosing not to have children may trigger the increase, said Rebecca Siegel, senior scientific director of surveillance research at the American Cancer Society. Having children before the age of 35 reduces the risk of breast cancer, as does breastfeeding.

However, he noted that there is a lot of year-to-year variation in diagnosis rates. Other researchers say the increase among young women may simply reflect more screening, said Steven Woloshin, MD, a professor of medicine at the University of Dartmouth in Massachusetts.

There is no consensus

Frequent screening can be harmful by leading to anxiety-inducing unnecessary biopsies and treatment for slow-growing cancers that are never fatal, researchers say. However, in 2009, criticism arose from patients and advocacy groups that the task force recommended that only women over 50 should receive routine mammograms.

Critics of the guideline feared that malignancies among young women would go unnoticed, and a desire to reduce healthcare costs led to the recommendation. At the time, the group called for longer intervals between mammograms: once every two years instead of annual exams. That recommendation still stands.

The American Cancer Society differs on this key point. The society says women between the ages of 40 and 44 can choose to be screened, but women should get mammograms starting at age 45 and every year until age 55, when the risk of breast cancer begins to decline.