How often should an average-risk woman have a mammogram?

This page is for women wondering how often to get a screening mammogram. It explains the current national recommendation, what changed, and who may need a different schedule.

For women at average risk, the US Preventive Services Task Force recommends a mammogram every two years, from age 40 through age 74.

The Task Force calls this biennial. That word just means every other year. They gave it a grade B, which is their rating for moderate net benefit.

Guidance in this area has shifted. That is a big reason why friends the same age have heard different things.

The 2024 recommendation replaced guidance from 2016. The older version treated screening in your forties as a personal choice, made with a doctor. The current version says all women should start screening at age 40.

If someone told you a decade ago that starting at 40 was optional, that was true at the time. It has since changed.

Past age 74, the Task Force did not make a call either way. It found that current evidence is not enough to weigh the benefits and harms of screening mammograms in women 75 and older. This is called an I statement.

It is easy to misread that as "screening stops at 75." It does not say that. It says the right studies have not been done yet to answer the question well.

Where evidence runs out, a personal talk with your doctor replaces a general rule.

For an older woman, that talk usually covers overall health, other conditions, and what she would want if something were found. Those are personal factors no general guideline can settle for you.

This guidance is written for women at average risk. The Task Force says its recommendation does not apply to people with a known high-risk gene change such as BRCA1 or BRCA2, past high-dose radiation to the chest at a young age, or a previous breast cancer or high-risk breast lesion on biopsy. A family history of breast cancer or dense breasts can also raise risk.

If any of those fit you, ask your doctor what schedule applies to you.

Screening has benefits, and it has costs. The Task Force weighs both.

The benefit is finding cancers earlier. The Task Force lists possible harms as false-positive results, extra testing and biopsies, overdiagnosis, and radiation exposure. It says evidence suggests biennial screening has a more favorable balance of benefits and harms than annual screening.

The Task Force found that two years balances those two things better than yearly screening for women in this age range. Other expert groups reach different conclusions. That is one more reason a personal talk is worth having, rather than assuming any single schedule is the only right one.

Guidelines only help if you actually book the appointment. Two small habits make a real difference. Put your next mammogram on the calendar the same day you go for this one. And keep track of where your past images were taken — comparing new scans to old ones truly helps a radiologist.

Patients often find that a medical group, a hospital website, and a friend's clinic all quote slightly different schedules. That is not carelessness. Different expert groups look at the same evidence and land on different judgment calls. The American Cancer Society, for example, says women 45 to 54 should get yearly mammograms and women 40 to 44 may choose to start yearly screening.

The Task Force's job is to review the evidence and rate the net benefit for one defined group of people. Their rating system is worth knowing. A grade B means they judged a moderate net benefit. An I statement means the evidence was not enough to judge at all.

If your doctor gives advice that differs from what you have read, ask why instead of assuming someone is wrong. Often the reason is specific to you — a family history, a past biopsy, dense tissue on an old scan. Hearing that reason helps more than any general schedule.

Write down the plan you and your doctor agree on. Guidelines change over time. Your own written plan is what you will actually follow.