Breast Cancer Linked to Pregnancy Weight

By PEGGY PECK, UPI Science News SAN FRANCISCO, Apr 09, 2002 (United Press International via COMTEX) -- Women who gain more than 38 pounds during pregnancy experience a 40 percent increased risk of breast cancer after menopause, compared to expectant mothers who gain 25 to 35 pounds, researchers reported Tuesday at the American Association for Cancer Research annual meeting.

Dr. Leena Hilakivi-Clarke of the Lombardi Cancer Center at Georgetown University in Washington said in western countries about "30 percent of women gain more than 38 pounds during pregnancy." Half of pregnant women hold weight gain to the recommended 25 to 35 pound limit, which poses no additional breast cancer risk after menopause.

Another 20 percent gain too little weight during pregnancy, which does not increase cancer risk but does pose a health danger to the fetus, Hilakivi-Clarke said in an interview with United Press International.

Women who gain more than 50 pounds during pregnancy will triple their risk of breast cancer after menopause if they do not lose the weight afterward, Hilakivi-Clarke added, although excess weight gain does not increase risk for breast cancer in premenopausal women.

Hilakivi-Clarke said one possible explanation for the link between pregnancy weight gain and later breast cancer is that "the weight gain comes at time when the breast is already vulnerable. It is generally accepted that estrogen is linked to breast cancer risks and estrogen levels are at their highest during pregnancy."

She said for each 2.2-pound weight increase, the corresponding increase in breast cancer risk was 3.9 percent when adjusted for body mass index before pregnancy. Moreover, women who retain extra weight after pregnancy and carry it with them into menopause have a greater risk than women who manage to lose the weight before menopause.

"My advice to women who gained 38 pounds or more during pregnancy is this -- lose that weight before menopause," Hilakivi-Clarke said.

The findings were based on an analysis of data from studies of 23,885 breast cancer patients in Finland. The first study selected 98 women who developed breast cancer before menopause, along with 392 age-matched controls. The second study selected 332 subjects, including 166 women who developed breast cancer at an average age of 58 and an equal number of age-matched controls.

Dr. Joyce O'Shaughnessy, a breast cancer specialist at Baylor-Sammons Cancer Center and U.S. Oncology in Dallas, said the report underlines the link between obesity and breast cancer.

"From a public health standpoint, this just gives further credence to the belief that we need to focus our prevention efforts on reducing obesity," O'Shaughnessy said.

In a related study, Dr. Margot Cleary of the Hormel Institute in Austin, Minn., reported that when leptin -- a gene associated with weight gain -- is added to either normal breast cells or malignant breast cancer cells it promotes cell growth.

"Adding leptin to breast cancer cells increased cell numbers by 160 percent," Cleary said, adding that leptin levels increase as weight increases. "So I think there is a clear correlation between the weight gain findings and the laboratory results with leptin."

O'Shaughnessy noted there are several pregnancy-related factors that can influence the risk for breast cancer. For example, a first pregnancy before age 20 reduces the risk for breast cancer, while a first pregnancy between ages 20 to 25 has no impact on breast cancer risk.

"A first pregnancy after age 30 increases breast cancer risk by about 40 percent, which is roughly equal to the risk associated with pregnancy weight gain," she said, adding that women who have never been pregnant experience about a 35 percent to 40 percent increased risk for breast cancer compared to women who have had at least one pregnancy.

Copyright: Copyright 2002 by United Press International.

Home Contents Grandma's Herbs Products Miracle Products Roex Products Shipping Policies

* These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure, or prevent any disease. This information is nutritional in nature and should not be construed as medical advice. This notice is required by the Federal Food, Drug and Cosmetic Act.

Copyright © 2010 Mindbodyhealth All rights reserved
Last modified: July 22, 2011