The original paper, which I had written in collaboration with colleagues from Penn State College of Medicine in Hershey, was published in the British Medical Association's Journal of Epidemiology and Community Health last October. My presentation in Ontario centered on several additional studies essentially confirming our original finding of 30% increased risk of breast cancer attributable to abortion. Nothing is more an article of faith for radical feminists such as Bella Abzug than that abortion is indispensable to women's equality.

Therefore I expected that the room would be largely empty -- especially given that there were five other concurrent sessions -- for such an against-the-grain presentation. But to my surprise, not only was the room full, but the attentive audience included Ms. Abzug herself.

As readers may recall, our meta-analysis found that 24 out of the 30 epidemiological studies published worldwide since 1957 have confirmed the abortion-breast cancer (ABC) link. More recent publications supporting and challenging the ABC link were discussed in my presentation in Kingston.

For one, there is the continuing heated debate about the Melbye study from Denmark published in this January's New England Journal of Medicine (NEJM). The U.S. National Cancer Institute and others continue to maintain that it disproved the ABC link. The World Conference provided me the opportunity to point out the serious flaws in the Melbye study, as had been done in an article published in National Right to Life News (5/23/97), and in a letter to the editor, which appeared in the June 19 edition of NEJM.

Among other egregious flaws, Melbye, et al., had misclassified some 60,000 women in the study as not having had any abortions who actually did have legal abortions on record!

For another, there was the Rookus study on Dutch women published last December in the Journal of the National Cancer Institute (JNCI). Readers may remember how the authors of this well-designed study found a 90% risk increase with abortion, but then proceeded to explain it away on the basis of something called "reporting bias".

This curious argument holds that the ABC link only appears to exist because women with breast cancer are more likely to admit having had abortions than are healthy women. As a result, they say, studies which depend on women reporting their reproductive histories (as most studies do) will show an artificially elevated risk.

The authors of the Dutch study claimed to have evidence of reporting bias. But as was demonstrated both to readers of NRL News (12/10/96) and readers of the April 12 edition of JNCI, by way of another letter to the editor, it was this so-called evidence which had been artificially manufactured.

It was the JNCI editorial that accompanied the Dutch study which the journal's editors (who are also high-ranking NCI officials) used to attack our meta-analysis by name. They claimed we had made "a leap beyond the bounds of inference" for inferring a causal link between abortion and breast cancer.

In our letter rebutting these charges, we pointed out how, rather than relying solely on the statistical link, a causal association was also supported by the biological facts, namely:

1. Estrogens are strong growth promoters of normal and most cancerous breast tissue.

2. Most known risk factors for breast cancer are attributable to some form of estrogen overexposure.

3. Maternal estradiol (estrogen) rises 20-fold (2,000%) during the first trimester of a normal pregnancy. [Estrogen makes breast tissue grow, including potentially cancerous tissue. If the pregnancy is completed, other hormones cause the breast tissue to differentiate into milk-producing tissue. If pregnancy isn't completed, the excess estrogen leaves the tissue free to grow into abnormal or even cancerous cells.]

4. But pregnancies which abort spontaneously (miscarry) usually generate subnormal amounts of estradiol; no increased risk of breast cancer is seen.

5. The incidence of breast cancer is dramatically increased in rats whose pregnancies are aborted."

It is of course outrageous that the Melbye study is being used to spread the claim that the ABC link does not exist. This is not good news for women, who are still actively being kept in the dark by the very agencies who should warn them about avoidable cancer risks.

In this regard, Dr. Patricia Hartge, author of the NEJM editorial which accompanied the Melbye study, is only the most recent National Cancer Institute researcher disparaging the link. However I find it encouraging that the ABC debate is finally out in the open.

I have already published a brief rebuttal in The Wall Street Journal, and co-authored another which is in press in the NEJM. The fact that Melbye, et al., did such a bad job will only hasten the day when the ABC link will be common knowledge. -jb


Dr. Brind's other works:

Sub-Committee Hearings-on "War on Cancer"
Dr. Brind's ABC Link at World Conference on Breast Cancer
Dr. Brind's review of the Melbye/Danish Report

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