The Link Between Breast Cancer and Abortion

The news about the dangers of abortion is getting out, despite suppression by scientists and other vested interests — in particular, the relationship of abortion and subsequent breast cancer in the youngest women, those under age 18. They should be informed about the abortion-breast cancer link, especially if they become pregnant unexpectedly.

Evidence for an abortion-breast cancer link continues to accumulate. In a recent exhaustive compilation and review of the evidence in the Summer 2005 issue of The National Catholic Bioethics Quarterly, Dr. Joel Brind, professor of Biology and Endocrinology at The City University of New York’s Baruch College, updates the evidence for and against the link.

Some of the most striking evidence is for the increased risk of breast cancer in young women. For example, the study by Dr. Janet Daling in 1994 found a statistically significant 50 percent higher incidence of breast cancer among women who had had induced abortions, compared with other women.

But among women under age 18 at the time of their first abortion, the increased incidence of breast cancer was 150 percent. And of these women under age 18, 12 also had a family history of breast cancer; among these 12, all had developed breast cancer before they reached age 45.

Women under age 18 who did not have a family history of breast cancer but whose abortions were performed after eight weeks of gestation suffered an 800 percent increase in breast cancer incidence.

An association of abortion with subsequent breast cancer is biologically plausible. Destroying a woman’s first pregancy with induced abortion abruptly cancels the normal transformation of breast tissue into mother’s-milk-producing tissue. During this transformation, hormones stimulate breast tissue cells to divide and multiply rapidly. After a baby’s birth, breast tissue begins producing milk, completing the change.

But interrupting the process in mid-course leaves many rapidly dividing breast cells not fully differentiated into milk-producing cells. Undifferentiated cells typically have higher potential for cancerous change. So it makes biological sense that breast tissue development interrupted by induced abortion would leave the tissue more prone to cancerous change later in life.

Hormone levels rise and fall much more gradually in pregancies ending in spontaneous miscarriages than with induced abortions. Women with spontaneous abortion (miscarriage) do not show increased incidence of breast cancer.

Although the Supreme Court made law by legalizing abortion in Roe v. Wade in 1973, the abortion-breast cancer link was not immediately apparent because most women having induced abortions are in their prime child-bearing years, from late teens to mid-30s, and most women developing breast cancer are older, in their 60s and 70s. In other words, it would take several decades for such a link to become manifest.

Nowadays, pharmaceutical manufacturers have to include a great deal of information in the insert they include in every package of medicine, including not only common side effects and adverse reactions but also every single thing that happened to anybody taking the medicine during clinical trials, whether related to the medicine or not. Although including insignificant or very rare reactions is excessive, pregnant women should at least be told about the the documented, statistically significant and biologically plausible associations of abortion with subsequent breast cancer.

Controversial evidence should not be ignored. As Dr. Jane Orient, executive director and past president of the Association of American Physicians and Surgeons, says, the elevated risk is “substantial, particularly in women who abort their first pregnancy at a young age and who have a family history of breast cancer.”

Some of these youngest women, under age 18, are barely adolescents. They deserve better protection than currently provided by American society and laws.

Editor’s Note: Robert J. Cihak wrote this week’s column.

Robert J. Cihak, M.D., is a Senior Fellow and Board Member of the Discovery Institute and a past president of the Association of American Physicians and Surgeons. Michael Arnold Glueck, M.D., is a multiple-award-winning writer who comments on medical-legal issues.



Dr. Robert J. Cihak, M.D.

Robert J. Cihak, M.D., was born in Yankton, South Dakota. He received his Bachelor's Degree from the University of Notre Dame, Indiana, where he studied under the philosopher Eric Voegelin. He earned an M.D. degree at Harvard Medical School (1962-66), and did postgraduate medical training and academic work as a surgical intern at Stanford Medical Center (1966-67), diagnostic radiology resident at the Massachusetts General Hospital (MGH) in Boston (1967-70) and Assistant Professor of Radiology, U. New Mexico Medical School, Albuquerque, (1970-71). He then practiced diagnostic radiology in Aberdeen Washington until his retirement in 1994.