Abortion’s Risk

Pro-choice groups should not fall into the trap of defending abortion as absolutely safe — it may not be.

During the second 100 days of Gingrich rule, brace yourself for what promises to be the most vehement attack on abortion yet: an attempt by the right to persuade Americans that abortion increases women’s risk of breast cancer. The battle lines are being drawn, and so far, most pro-choice groups have played right into Newt’s hands.

The brouhaha began last November, when the Journal of the National Cancer Institute published a study by epidemiologists at Seattle’s Fred Hutchinson Cancer Research Center showing that for women under 45, induced abortion doubles breast cancer risk. “Approximately 1 woman in 100 develops breast cancer by age 45,” says Janet Daling, the study’s lead researcher. “Abortion raises that risk to about 2 per 100.”

The risk depends, in part, on a woman’s lifetime exposure to estrogen and the changes the hormone triggers in breast cells (see “Breast Cancer Cover-up,” May/June 1994). Reproductive events–age of first menses, childbearing and breast-feeding history, age at menopause, spontaneous (miscarriage) and induced abortion experience–all affect estrogen exposure, breast-cell development, and breast cancer risk, as do environmental factors, such as exposure to organochlorines.

Anti-abortion forces who got wind of Daling’s study fired off op-ed pieces like the one by Lynn Murphy in the San Francisco Chronicle, who hailed the report as “the 26th study [sic] showing that abortion greatly increases risk of breast cancer.” Murphy urged “a moratorium on abortion until it’s proven safe.”

Unfortunately, most pro-choice groups have focused on the study’s potential bias and limitations. With the exception of a few balanced fact sheets by some women’s health organizations, pro-choice groups either dismiss the alleged association or concede the possibility of increased risk but call it “infinitesimal.”

Such denials do a disservice to women and set pro-choice groups up as sitting ducks for GOP sharpshooters. Women deserve the facts. A Mother Jones search of the medical literature (from 1985 to the present) uncovered 24 studies dealing with abortion as a possible risk factor for breast cancer. The findings were mixed.

Nine studies show that induced abortion may increase the risk of contracting breast cancer, by as little as 10 percent to as much as 100 percent; 4 studies of spontaneous abortions show they increase risk. Abortion before a first full-term pregnancy appears to increase risk the most (1 study shows risk increasing with the number of abortions). Eight studies, 7 of which were of induced abortions, show no increased risk. Finally, 3 studies show that abortion decreases breast cancer risk.

At least four more studies are in progress; preliminary data from two suggest that abortion does increase breast cancer risk.

If abortion is linked to breast cancer, the risk increase appears to be modest, on the order of that observed in women who have taken the pill for many years or used postmenopausal estrogen replacement therapy (ERT), or who had their first period before 12, their first child after 30, or no children at all. The risk increase appears much less significant than the risk of having a mother or sister with the disease.

When the right starts advocating a “moratorium on abortion until it’s proven safe,” progressives should infuse the debate with something it has largely lacked–perspective. Pro-choice groups should not fall into the trap of defending abortion as absolutely safe. It may not be. Women should have access to all information that affects their health–and the right to choose what to do. For example, ERT may increase breast cancer risk, but it decreases risk of heart attack, making it a reasonable, in fact, potentially lifesaving choice for many women.

And Newt and his pals should not be allowed to frame the debate within the narrow construct of banning abortion. Congressional hearings must address our broader obligation to investigate all causes of breast cancer, and to find a cure.



Mother Jones was founded as a nonprofit in 1976 because we knew corporations and the wealthy wouldn't fund the type of hard-hitting journalism we set out to do.

Today, reader support makes up about two-thirds of our budget, allows us to dig deep on stories that matter, and lets us keep our reporting free for everyone. If you value what you get from Mother Jones, please join us with a tax-deductible donation today so we can keep on doing the type of journalism 2019 demands.

We Recommend


Sign up for our newsletters

Subscribe and we'll send Mother Jones straight to your inbox.

Get our award-winning magazine

Save big on a full year of investigations, ideas, and insights.


Support our journalism

Help Mother Jones' reporters dig deep with a tax-deductible donation.


We have a new comment system! We are now using Coral, from Vox Media, for comments on all new articles. We'd love your feedback.