Studies - Breast Cancer

Abortion More Than Tripled Breast Cancer Risk& Breastfeeding Reduces Risk (CE, 3/2010… updated)

Study: Abortion More Than Tripled Breast Cancer Risk for Sri Lankan Women
AND Prolonged Breastfeeding Reduces Risk of Breast Cancer in Sri Lankan Women: a Case-Control Study 

A new study out of Sri Lanka has found that women who had abortions more than tripled their risk of breast cancer.

The study focused on analyzing the association between the duration of breastfeeding and the risk of breast cancer.

But the researchers also reported other “significant” risk factors for breast cancer, such as exposure to passive smoking and being post-menopausal.

The highest of the reported risk factors was abortion.

The study, entitled "Prolonged breastfeeding reduces risk of breast cancer in Sri Lankan women: A case-control study," was led by Malintha De Silva and colleagues from the University of Colombo.

The researchers found that among women who breastfed for between 12-23 months there was a 66.3% risk reduction in comparison to those who had never breastfed and those who breastfed for between 0 and 11 months. The risk reduction climbed to 87.4% for those who breastfed for 24-35 months and 94% among women who breastfed for 36-47 months.

Dr. Joel Brind, an epidemiologist at the City University of New York, cautioned that the researchers do not clearly indicate whether they are referring specifically to induced abortions, as opposed to spontaneous abortions (miscarriage).  Requests for clarification have not yet been answered.

However, in the study the researchers compare their findings with other studies that focused on induced abortions, seeming to suggest that induced abortion was their focus.

According to Dr. Brind, an expert on the association of abortion and breast cancer, the findings are consistent with studies from other populations where abortion rates are low. He explained that in epidemiology, risk factors are best analyzed in places where the particular factor is less prevalent. Once most people have that factor, however, it is much more difficult to study its influence, since it is difficult to find anyone with whom to compare.

“This study is consistent with the kind of data we used to see in China and Japan when abortion had a very low prevalence,” he said.  But in China, where abortion has become rampant, research is now showing a higher risk of breast cancer following abortion.

Dr. Brind said that the study’s raw data supports the conclusion about the abortion-breast cancer link.  But he criticized the paper about the study, which he said “has some errors in it which should have been corrected on peer review.”

Most significantly, he highlighted the researchers’ claim that a late age at first pregnancy strongly decreased the risk of breast cancer, which goes against all the other research over the last 50 years.  “This is not a valid finding,” he said, because the researchers “actually miscalculated their own raw data.”

Karen Malec, president of the Coalition on Abortion/Breast Cancer, said that the study shows that "women who abort forfeit the protective effect of breastfeeding.”

“The loss of that protective effect is incurred in addition to the effect of abortion leaving the breasts with more places for cancers to start.”

Malec said that given the lack of routine mammograms in Sri Lanka, “health professionals must focus on disease prevention,” which would involve publicizing the link between abortion and breast cancer.

“It is criminal that the U.S. National Cancer Institute (NCI) has covered up this risk for over a half century," she said.

However, she continued, "It's becoming increasingly difficult for the NCI to keep its fingers and toes in the dike,” in large part because “many researchers in other parts of the world do not depend on the agency for grants."

The Sri Lankan study is the fourth epidemiological study in the last 14 months to report an abortion-breast cancer link. The three other studies have come out of the U.S., China and Turkey.  Louise Brinton, a NCI branch chief, served as co-author in the U.S. study in which she and her colleagues admitted that "…induced abortion and oral contraceptive use were associated with increased risk of breast cancer." The authors cited a statistically significant 40% increased risk.

National Cancer Institute Researcher Admits Abortion Breast Cancer Link
http://www.lifesitenews.com/ldn/2010/jan/10010706.html
[Jun 22, 2010, Patrick B. Craine, COLOMBO, Sri Lanka, http://www.lifesitenews.com/news/archive//ldn/2010/jun/10062202]

[Cancer Epidemiol. 2010 Jun;34(3):267-73. Epub 2010 Mar 24. "Prolonged breastfeeding reduces risk of breast cancer in Sri Lankan women: a case-control study". De Silva M, Senarath U, Gunatilake M, Lokuhetty D. ; http://www.lifesitenews.com/ldn/2010/jun/10062202.html ; ALL Pro-Life Today | 22 June 2010]

 Prolonged Breastfeeding Reduces Risk of Breast Cancer in Sri Lankan Women: a Case-Control Study

Abstract
GOAL:
To assess the association between duration of breastfeeding and the risk of breast cancer in Sri Lankan women.

METHODS:
We conducted a case-control study in women aged 30-64 years in selected health care facilities in the Western province. A total of 100 recent cases of breast cancer (histologically confirmed) and 203 controls (age and parity matched) were included. Detailed information regarding breastfeeding, menstruation, reproductive factors, passive smoking and other confounders was collected using a structured questionnaire. Adjusted odds ratios and 95% confidence intervals were calculated using multiple logistic regressions.

PRINCIPLE RESULTS:
Multivariate analysis found that those women who breastfed for > or =24 months during lifetime had significantly lower risk of breast cancer than those who breastfed for less than 24 months (OR=0.40; 95%CI=0.22, 0.73). Compared to 0-11 months of lifetime breastfeeding, there was a 66.3% reduction in breast cancer risk in women who breastfed for 12-23 months, 87.4% reduction in 24-35 months and 94% reduction in 36-47 months categories. The mean duration of breastfeeding per child for > or =12 months was also associated with reduced risk of breast cancer (OR=0.52; 95%CI=0.28, 0.94). The significant factors associated with increased risk of breast cancer were: post-menopausal women (OR=1.74; 95%CI=1.01, 3.01); having an abortion in the past (OR=3.42; 95%CI=1.75, 6.66) and exposure to passive smoking (OR=2.96, 95%CI=1.53, 5.75).

MAJOR CONCLUSIONS:
Prolonged breastfeeding significantly reduces the risk of breast cancer and this protective effect was supported by a dose-response relationship. Risk due to passive smoking should be emphasized in anti-smoking programmes.

Copyright (c) 2010 Elsevier Ltd. All rights reserved.

PMID:
    20338838
    [PubMed – indexed for MEDLINE]
Cancer Epidemiol. 2010 Jun;34(3):267-73. doi: 10.1016/j.canep.2010.02.012. Epub 2010 Mar 24., De Silva M, Senarath U, Gunatilake M, Lokuhetty D.
Source: Department of Community Medicine, Faculty of Medicin

e, University of Colombo, 25 Kynsey Road, Colombo, Sri Lanka.
http://www.ncbi.nlm.nih.gov/pubmed/20338838

Find entire study paper at — http://www.issues4life.org/pdfs/20100226_prolonged.pdf