Childbearing Raises Type Of Breast Cancer Risk Among African American Women, Breastfeeding Reduces Risk

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Main Category: Breast Cancer
Also Included In: Women's Health / Gynecology;  Pregnancy / Obstetrics
Article Date: 16 Aug 2011 - 22:00 PDT


Childbearing can increase an African-American woman's likelihood of developing hormone receptor-negative breast cancer, but her risk is reduced if she breastfeeds, researchers from Boston University reported in Cancer Epidemiology, Biomarkers & Prevention. Hormone receptor-negative breast cancer is one of the hardest subtypes to treat.

Hormone receptor-negative breast cancer is also known as ER-negative breast cancer ("ER" stands for "Estrogen Receptor").

Senior author, Julie Palmer, Sc.D., said:

"African-American women are more likely to have had a greater number of full-term births and less likely to have breast-fed their babies. This study shows a clear link between that and hormone receptor-negative breast cancer."

Palmer and team had set out to determine whether childbirth and breastfeeding might impact on breast cancer risk. They gathered data on 59,000 African-American women who had participated in the Black Women's Health Study from 1995 to 2009.

The participants initially completed a questionnaire which included questions on childbirth and breastfeeding. They also filled in a questionnaire every 24 months, which included questions on whether they had been diagnosed with breast cancer.

The researchers identified 547 cases of ER-positive breast cancer and 318 with ER-negative breast cancer.

They found that women who had had at least two children had a 50% higher chance of developing hormone receptor-negative breast cancer.

They also noted that among the women with at least two children who breastfed, the increased risk was no longer significant.

Palmer said:

"The adverse effect of high childbirth without subsequent breast-feeding seems to be confined to the hormone receptor-negative breast cancer, which carries a higher mortality rate and is more common in African-Americans."

Written by Christian Nordqvist
Copyright: Medical News Today
Not to be reproduced without permission of Medical News Today

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