In 2004 the Collaborative Group on Hormonal Factors in Breast Cancer evaluated the worldwide epidemiological evidence on the possible relation between breast cancer and previous spontaneous and induced abortion ad found no link. The results, drawn from 53 studies, were published in the Lancet.
A new study confirms this data, that there is no link between abortion and breast cancer. The data come from a study of over 25,000 Danish women from the DIet, Cancer, and Health study. The women completed questionnaires and then were followed for an average of 12 years. This kind of study is probably the best way to look at two common and emotional charged occurrences, like abortion and breast cancer, because there is no recall bias. When something bad happens it is human nature to look back and try to assign causality, but collecting the data prospectively removes this element. The study was also well-powered to detect even a small increase, so another plus.
On one hand we have a mountain of high-quality evidence (facts) that tells us there is no link between abortion and breast cancer, but yet we have lawmakers who continue to try to tie the two together in what can only be described as reproductive blackmail. Take the Kansas Women’s Right to Know Act, designed to “inform” women (I use the word information rather loosely in this context as it should really be called the Kansas Women’s Right to be Lied to by Their State government Act). It contains double speak about breast cancer and abortion of Orwellian proportion:
- There are also studies that have found an increased risk of breast cancer after induced abortion, but other studies have found no risk. A 2003 National Cancer Institute panel reviewing studies at that time concluded there was no increased risk; however, study and review of the relationship continue. NCI recognizes research that shows pregnancy and breastfeeding both reduce a woman’s lifetime cumulative exposure to hormones that otherwise might increase her risk of breast cancer. Pregnancy and breastfeeding also cause breast cells to mature in order to produce milk, and some researchers hypothesize those cells are more resistant to cancer.
Now contrast that to the information on the National Cancer Institute’s website:
- In February 2003, the National Cancer Institute (NCI) convened a workshop of over 100 of the world’s leading experts who study pregnancy and breast cancer risk. Workshop participants reviewed existing population-based, clinical, and animal studies on the relationship between pregnancy and breast cancer risk, including studies of induced and spontaneous abortions. They concluded that having an abortion or miscarriage does not increase a woman’s subsequent risk of developing breast cancer. A summary of their findings can be found in the Summary Report: Early Reproductive Events and Breast Cancer Workshop.NCI regularly reviews and analyzes the scientific literature on many topics, including various risk factors for breast cancer. Considering the body of literature that has been published since 2003, when NCI held this extensive workshop on early reproductive events and cancer, the evidence overall still does not support early termination of pregnancy as a cause of breast cancer. To view regular updates on this topic, please go to the Breast Cancer PDQ® summary, which is part of NCI’s comprehensive database.
The studies that “found” an association between breast cancer and abortion were flawed and have since been disproven by the National Cancer Institute, the published Lancet review, a myriad of other studies, and the latest study that I referenced above. Using discredited/flawed data to make your case is like saying in 2013 that we know the earth is flat because someone proved it to be so in 1321 and to ignore everything published on astronomy, physics, and space exploration since.
It’s a shame that we need more studies to prove what we already know. But until state governments and organizations like the American Association of Pro-life OB/GYNs believe that science is a more important guiding principle than religious belief, we have no other option. To say there is causative link between abortion and breast cancer isn’t just stretching the truth, it’s a lie.