a1 Department of History, Lakehead University, 955 Oliver Road, Thunder Bay, Ontario, Canada P7B 5E1
Epidemiology, like any branch of medical science, functions within a social and historical context. That context influences what questions are asked, how they are investigated, and how their conclusions are interpreted, both by researchers and by the public. The international debate over whether abortion increases breast cancer risk, which has been the subject of many studies and much heated controversy in recent decades, became so intensely politicized in the United States that it serves as a particularly stark illustration of how elusive the quest for scientific certainty can be. Although a growing interest in reproductive factors and breast cancer risk developed after the Second World War, it was not until the early 1980s, after induced abortion had been legalized in many countries, that studies began to focus on this specific factor. In the US these were the years following Roe v Wade, when anti-abortionists mounted their counterattack and pro-choice forces were on the defensive. As a result, epidemiologists found themselves at the centre of a debate which had come to symbolize a deepening divide in American culture. This paper traces the history of the scientific investigation of the alleged abortion-breast cancer link, against the backdrop of what was increasingly termed an “epidemic” of breast cancer in the US. That history, in turn, is closely intertwined with the anti-abortion movement's efforts, following the violence of the early 1990s, to regain respectability through changing its tactics and rhetoric, which included the adoption of the “ABC link” as part of its new “women-centred” strategy.