Find Information About:

Drugs & Supplements

Get information and reviews on prescription drugs, over-the-counter medications, vitamins, and supplements. Search by name or medical condition.

Pill Identifier

Pill Identifier

Having trouble identifying your pills?

Enter the shape, color, or imprint of your prescription or OTC drug. Our pill identification tool will display pictures that you can compare to your pill.

Get Started
My Medicine

My Medicine

Save your medicine, check interactions, sign up for FDA alerts, create family profiles and more.

Get Started

WebMD Health Experts and Community

Talk to health experts and other people like you in WebMD's Communities. It's a safe forum where you can create or participate in support groups and discussions about health topics that interest you.

  • Second Opinion

    Second Opinion

    Read expert perspectives on popular health topics.

  • Community


    Connect with people like you, and get expert guidance on living a healthy life.

Got a health question? Get answers provided by leading organizations, doctors, and experts.

Get Answers

Sign up to receive WebMD's award-winning content delivered to your inbox.

Sign Up

Women's Health

Font Size

With Mammograms, Timing May Matter

For Women Who Get Regular Mammograms, Scheduling the First Week of Cycle Seems Best, Study Finds
WebMD Health News
Reviewed by Louise Chang, MD

Dec. 14, 2010 -- Women who have regular mammograms should consider paying attention to when they are scheduled. New research finds the timing of mammograms could affect the accuracy of results.

''Try to schedule it during the first week of your menstrual cycle," says researcher Diana Miglioretti, PhD, a senior investigator at Group Health Research Institute in Seattle, who led the study. "The first day of your menstrual cycle is the day you start to bleed."

But she adds: "I don't want women to stress too much over this, if they can't get in."

Her study does show, however, that timing of mammograms can make a difference for women who regularly get them. For some reason, the timing did not seem to have the same effect on accuracy in the women studied who were getting their first mammogram, Miglioretti tells WebMD.

The study is published online in the journal Radiology.

Timing of Mammograms: Backstory

Previous studies have looked at the timing of mammograms, Miglioretti says. Some experts have found that accuracy might be better in the first half of the cycle.

Other research has shown that breast density may be lower during the first half of the cycle. "We know breast density strongly affects mammography performance," she says. If a woman has a lot of dense tissue, it's more difficult to find cancer.

Timing of Mammograms: Study Details

Miglioretti and her colleagues examined 387,218 mammograms from women aged 35 to 54 who got the screenings from 1996 through 2007. The data were retrieved from six National Cancer Institute-funded Breast Cancer Surveillance Consortium mammography registries.

None of the women had a history of breast cancer, breast augmentation, or mastectomies. The images were interpreted by more than 770 radiologists.

In all, 1,283 of the mammograms were linked to breast cancer cases.

The researchers took into account when the women had the mammograms and whether it was their first or not. They found that for women who had already had a screening mammogram in the past two years, the sensitivity -- the number of true positive findings -- was highest in those who had the mammograms the first week of their cycle. ''It was about 80% the first week," Miglioretti says.

Today on WebMD

hands on abdomen
Test your knowledge.
womans hand on abdomen
Are you ready for baby?
birth control pills
Learn about your options.
Is it menopause or something else?
woman in bathtub
bp app on smartwatch and phone
estrogen gene

Send yourself a link to download the app.

Loading ...

Please wait...

This feature is temporarily unavailable. Please try again later.


Now check your email account on your mobile phone to download your new app.

Blood pressure check
hot water bottle on stomach
Attractive young woman standing in front of mirror