Screening & Gynecologic Cancer

Mammogram Guidelines: Why Screening Now Starts at 40 and How Often to Go

By the Find Her Doctor editorial team · Updated November 1, 2026 · 5 min read

If you're at average risk of breast cancer, start mammograms at 40. In April 2024 the U.S. Preventive Services Task Force (USPSTF) recommended screening every 2 years from 40 to 74, and ACOG and the American Cancer Society also support yearly screening for people who prefer it. If your risk is higher, you may need to start earlier.

What changed in 2024

Before 2024, the USPSTF called screening in your 40s an individual choice and recommended routine screening every 2 years from 50 to 74. The update lowered the starting age to 40, for two main reasons:

• Breast cancer rates in people in their 40s have been rising.
• Modeling showed that starting at 40 prevents more deaths, with the biggest benefit for Black women, who are more likely to die of breast cancer and more likely to be diagnosed younger.

If a doctor told you a few years ago to "wait until 50," that advice is out of date. It's worth asking again.

How the major guidelines compare

They all agree screening should be available from 40. They differ on how often.

Yearly or every other year? Talk it through with your clinician. Yearly screening may catch some cancers earlier; every other year means fewer callbacks and false alarms.

Who should start before 40?

These guidelines are for average risk. You may need earlier or extra screening, often including breast MRI, if you:

• Carry a BRCA1, BRCA2 or other high-risk gene variant
• Have a parent, sibling or child with a known BRCA variant and haven't been tested
• Had radiation to the chest between ages 10 and 30
• Have a lifetime breast cancer risk of about 20% or higher on a risk model
• Have certain high-risk breast biopsy results

Your clinician can estimate your risk from your family history and other factors, ideally by your 30s. Bring what you know: who in the family had breast, ovarian, pancreatic or prostate cancer, and at what age. If hereditary cancer runs in your family, see our guide to BRCA genetic testing.

Your first mammogram, start to finish

1. You undress from the waist up and put on a gown. Wear a top and pants or a skirt, not a dress, so you only change half.
2. A technologist positions one breast at a time on the machine.
3. A plastic plate presses the breast flat for a few seconds while the image is taken.
4. Usually two images per breast. The whole thing often takes about 15 to 20 minutes once you're called in.

The squeeze is uncomfortable for many people, sometimes sharply, but each one lasts only seconds. Tell the technologist if it hurts too much; they can often adjust.

Tips that help:

• Book for the week after your period, when breasts are less tender.
• Skip deodorant, lotion and powder that day. They can show up as specks on the images. Many centers keep wipes on hand if you forget.
• Bring prior mammograms, or tell the center where you had them, so they can compare. Comparison is one of the best ways to cut down on callbacks.

"They called me back." Now what?

This is the moment that scares people most, and it's common, especially after a first mammogram when there's nothing to compare against. Most callbacks turn out to be normal or benign. You might get more mammogram views or an ultrasound. A biopsy happens only if something still looks concerning after that.

When do results come?

A radiologist reads your images, often within a few days. Under federal law, facilities must send you a plain-language summary of your results. Many centers also post them to a patient portal. If you haven't heard anything within two weeks, call the imaging center. Don't assume no news is good news.

3D mammograms

A 3D mammogram (digital breast tomosynthesis) takes many images from different angles and builds a layered picture of the breast. Compared with 2D, studies suggest it may find slightly more cancers and lead to fewer callbacks for some people, especially those with dense breasts. The USPSTF accepts either for routine screening, and many New York imaging centers now offer 3D as standard.

Dense breasts

About half of people 40 and older have dense breasts. Dense tissue can hide cancers on a mammogram and is linked to a slightly higher risk. Under both New York law and federal rules, your mammogram report must tell you if your breasts are dense.

The USPSTF found there isn't enough evidence yet to recommend extra screening for everyone with dense breasts, but some people may benefit from ultrasound or MRI. Read our guide to dense breasts and New York's notification law.

What it costs in New York

Under the Affordable Care Act, most private plans cover screening mammograms with no cost-sharing. New York goes further. A 2016 state law removed cost-sharing for screening mammograms and for diagnostic imaging used to detect breast cancer, including diagnostic mammograms, breast ultrasound and breast MRI, in state-regulated plans, when your insurer considers the test medically necessary and you use an in-network provider. That matters, because the follow-up after a callback is where surprise bills used to hit.

Limits to know:

• Self-funded employer plans follow federal rules, not New York insurance law. Ask HR.
• Medicaid isn't part of that state law, but NY Medicaid generally doesn't charge cost-sharing for these services.

Uninsured? The New York State Cancer Services Program offers free screening to eligible New Yorkers. Your county health department can connect you.

When to see a doctor

Screening is for people with no symptoms. See a clinician promptly, no matter when your last mammogram was, if you notice:

• A new lump or thickening in the breast or underarm
• Skin dimpling, puckering, redness or an orange-peel texture
• A nipple that's newly turned inward
• Bloody or spontaneous nipple discharge
• Pain in one spot that doesn't go away

You'll usually need a diagnostic mammogram and ultrasound, not a screening one, so tell the scheduler about the symptom when you book.

Your next step

If you're 40 or older and haven't had a mammogram, book a well-woman visit and ask for a referral, or ask whether your local imaging center takes self-referrals. Search our directory or browse providers in Nassau County and Suffolk County.

Frequently asked questions

Sources

• USPSTF — Breast Cancer: Screening (2024 Final Recommendation Statement)
• ACOG — Breast Cancer Risk Assessment and Screening in Average-Risk Women (Practice Bulletin and 2024 Practice Advisory)
• American Cancer Society — Recommendations for the Early Detection of Breast Cancer
• National Cancer Institute — Mammograms
• New York State Department of Health — Breast Cancer Screening Law FAQs

This article is for general education and is not medical advice. It does not replace an evaluation by a licensed clinician who knows your history. If you think you have a medical emergency, call 911.