Study Dispels Abortion-Breast Cancer Link
Findings Show Abortion Doesn't Raise Breast Cancer Risk
Researchers have been studying the relationship between abortion and breast cancer for nearly 50 years. Until the mid-1990s, studies on the issue had produced inconsistent results, and most of the studies were considered flawed because they involved a small number of women and many studies collected information only after breast cancer had been diagnosed.
In 1996, Joel Brind, PhD, a professor of biology and endocrinology at Baruch College of the City University of New York, published a study based on 23 independent studies that asked women with and without breast cancer whether they had ever had an abortion.
Brind's study suggested that having had an abortion increased a woman's risk of breast cancer.
But Brind takes issue with the Beral's study and says the studies used in the analysis are also flawed.
Brind tells WebMD that studies that collect data prospectively tend to have huge gaps of information within the data. He says this leads to flawed results and conclusions.
"The prevalence of abortion is underestimated such that many, many women ... who had an induced abortion who are in that study are in fact known and proved to be misclassified as not having had an induced abortion."
But Brind says when those studies appear in internationally recognized medical journals, "people take them as gospel."
"In a non-politically sensitive field, such junk science would never make it into high-quality ... journals like that," says Brind.
Since Brind's study was published, a variety of medical and government organizations have conducted extensive reviews of the available research on the relationship between breast cancer and abortion and excluded any cause-and-effect relationship between the two.
- February 2003: An international scientific panel convened by the National Cancer Institute concluded that having an abortion or miscarriage "does not increase a woman's subsequent risk of developing breast cancer."
- August 2003: The American College of Obstetricians and Gynecologists concluded that although studies on the issue were inconsistent and difficult to interpret, mainly due to study design flaws, "there is no evidence supporting a causal link between induced abortion and subsequent development of breast cancer."
- September 2003: The American Cancer Society updated the cancer reference information on its web site to include the above findings and concluded, "At the present time, the scientific evidence does not support a causal association between induced abortion and breast cancer."
With the overwhelming agreement of major health organizations and inherent complexity of conducting research on this issue, Beral says her study should come as close as researchers can possibly get to providing a conclusive answer to the big question.
"This rules out short-term pregnancies ending in abortion as having a major role in breast cancer," Beral tells WebMD.