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

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

Cancer Health Center

Font Size

Endometrial Cancer Prevention (PDQ®): Prevention - Health Professional Information [NCI] - Description of Evidence


Factors Associated With Decreased Risk

Increasing parity and lactation

Decreased risk of endometrial cancer is associated with parity and lactation, perhaps by inhibiting ovulation. A case-control study conducted in Mexico City, among low-risk women, indicates a 58% to 72% reduction in risk of endometrial cancer associated with increasing duration of lactation. A significant trend was seen for duration of lactation and for the number of children breastfed.[28] A population-based case-control study, comparing Wisconsin women who breastfed for at least 2 weeks versus those who did not, was negative (OR = 0.90; 95% CI, 0.72-1.13). Increasing duration of lactation was not associated with a decrease in disease risk, but breastfeeding within the past three decades was associated with reduced risk (OR = 0.58; 95% CI, 0.36-0.96), as was the first breastfeeding after age 30 years (95% CI, 0.28-0.90).[29] The European Prospective Investigation into Cancer and Nutrition observed a decreased risk associated with parity compared with nulliparous women (hazard ratio = 0.65; 95% CI, 0.54-0.77) with a trend of decreasing risk with increasing number of full-term pregnancies (P < .0001). While breastfeeding for more than 18 months was associated with a decreased risk, the association attenuated and was no longer statistically significant after adjusting for the numbers of full-term pregnancies.[30]

Factors Associated With Increased Risk

Endogenous estrogen

Reproductive factors resulting in increased duration of exposure to endogenous estrogen, such as early menarche, nulliparity, and late menopause, are associated with an increased risk of endometrial cancer. Other factors associated with increased risk, such as obesity and polycystic ovary syndrome, may also be related to increased estrogen exposure.

The first prospective investigation of endogenous estrogens and the risk of endometrial cancer was a case-control study nested within the New York University Women's Health Study.[31] Results suggest an increased risk of endometrial cancer associated with postmenopausal levels of endogenous hormones including estradiol, percent-free estradiol, and estrone. Conversely, risk was decreased with higher levels of percent sex hormone-binding globulin (SHBG)-bound estradiol and SHBG. Analyses conducted prior to adjustment for hormone levels indicated a positive association with body mass index (BMI). After adjustment for estrone level, the positive association of BMI with risk of endometrial cancer was attenuated, suggesting that hormone levels may be an intermediate effect of body weight.[32]

Next Article:

Today on WebMD

Colorectal cancer cells
New! I AM Not Cancer Facebook Group
Lung cancer xray
See it in pictures, plus read the facts.
sauteed cherry tomatoes
Fight cancer one plate at a time.
Ovarian cancer illustration
Real Cancer Perspectives
Jennifer Goodman Linn self-portrait
what is your cancer risk
colorectal cancer treatment advances
breast cancer overview slideshow
prostate cancer overview
lung cancer overview slideshow
ovarian cancer overview slideshow
Actor Michael Douglas