FILE - In this Tuesday, July 31, 2012, file photo, a radiologist compares an image from earlier, 2-D technology mammogram to the new 3-D Digital Breast Tomosynthesis mammography in Wichita Falls, Texas. The technology can detect much smaller cancers earlier. In guidelines published Tuesday, Oct. 20, 2015, the American Cancer Society revised its advice on who should get mammograms and when, recommending annual screenings for women at age 45 instead of 40 and switching to every other year at age 55. The advice is for women at average risk for breast cancer. Doctors generally recommend more intensive screening for higher-risk women.

CHICAGO — The American Cancer Society now says women should start mammograms later in life and get fewer of them, a stance that puts the trusted group closer to an influential government task force’s advice.

In new guidelines out Tuesday, the cancer society recommends that most women should begin annual screening for breast cancer at age 45 instead of 40, and switch to every other year at 55. The task force advises screening every other year starting at age 50.

It’s not a one-size-fits-all recommendation; both groups say women’s preferences for when to be scanned should be considered.

The advice is for women at average risk for breast cancer. Doctors generally recommend more intensive screening for higher-risk women, including those with specific genetic mutations.

“The most important message of all is that a mammogram is the most effective thing that a woman can do to reduce her chance of dying from breast cancer,” said Dr. Richard Wender, the cancer society’s cancer control chief.

“It’s not that mammograms are ineffective in younger women,” he said, but at age 40, breast cancer is uncommon and false alarms are more likely. “Therefore, you’d have to do a lot more mammograms to prevent one death,” compared to older women, Wender said.

Concern about false alarms contributed to the cancer society’s new guidance. These lead to worry and more testing — they mean an initial result was suspicious but that cancer was ruled out by additional scans and sometimes biopsies.

The latest guidelines acknowledge that some younger women are willing to accept that, and that for them starting annual exams at age 40 is fine, as long as they know the risks.

The guidelines were developed by experts who reviewed dozens of studies including research published since 1997 — the year the cancer group recommended yearly mammograms starting at age 40, and since 2003, when it stopped recommending monthly breast self-exams.

The update recommends that women continue getting screened as long as they are in good health and have a life expectancy of at least 10 years. The old guidelines did not include an age limit.

The cancer group also dropped a recommendation for routine physical breast exams by doctors, saying there’s no evidence that these save lives.

The Rev. Jennifer Munroe-Nathans, 46, a pastor in Millis, Mass., said she hasn’t paid attention to guidelines and started getting annual scans around age 40 on her doctor’s advice. Her mother had breast cancer, so have some of her congregants and Munroe-Nathans said she has no plans to change course when she gets older.

“For my own peace of mind I intend to continue yearly mammograms,” she said. “I’ve seen the impact of breast cancer — perhaps that makes me a little more hyper-vigilant.”