Healthy Women, Healthy Lives A Guide to Preventing Disease from the Landmark Nurses' Health Study

Chapter Two: What Is the Nurses' Health Study? The Nurses' Health StudyThe Question That Got Us Started: "Do Birth Control Pills Have Long-Term Health Effects?"More than twenty-five years ago, this question sparked the beginning of what has since become one of the largest and most comprehensive studies of women's health. From birth control pills to exercise, from alcohol to zinc, the Nurses' Health Study has helped to identify many of the factors that protect health, as well as those that contribute to disease.The study began in the mid-1970s, when birth control pills had been in widespread use for about a decade. Pleased with their effectiveness and convenience, many women were intending to use the pills for decades to come. Yet there was considerable uncertainty about whether this practice was safe. Taking the pill had already been shown to increase the risk of blood clots, heart attacks, and stroke. And as other side effects of the pill began to emerge, researchers also suspected a link with breast cancer. It was the possibility of this last link that led us to propose a bold new study: we would survey thousands of women about their method of birth control and then track their health status over time.Because birth control pills were quickly emerging as a public health issue, the National Institutes of Health (the federal agency primarily responsible for prioritizing and funding medical research in the United States) was willing to consider funding our study. However, they first required that we submit a grant proposal so that our scientific peers could review what we had done so far -- and what we planned to do if our study was funded. We submitted a grant proposal in 1973 and received the funding to start the study in 1974. After two years of pilot-testing the methods for the study, we began recruiting participants in 1976.FINDING THE NURSESOur first major challenge was to identify a large group of women -- ideally tens of thousands -- who would be willing to complete a questionnaire about their method of birth control and their health status. In addition, the information they provided had to be accurate, and we had to be able to follow the women over time to determine if the pill had any long-term effects.We realized that nurses would be the ideal study participants -- and in fact they have been. As health professionals, they are extremely aware of the value of medical research and have thus been willing to make a long-term commitment to the study. In addition, they have been relatively easy to follow over the past twenty-five years, largely because they are prompt in notifying us of address changes. Finally, and perhaps most important, because of their knowledge and training, the nurses have been able to provide us with health information that is both accurate and reliable. This accuracy has been documented repeatedly. For example, whenever a study participant reports that she has been diagnosed with a serious illness, we ask permission to review her medical records to both confirm the diagnosis and gather additional details about the disease. The vast majority of the time we find that the nurse has provided us with accurate information.BEGINNING THE STUDYHaving chosen nurses as our study participants, we contacted the boards of nursing in eleven U.S. states and obtained the names and addresses of 170,000 female nurses. They were all married and between the ages of thirty and fifty-five to ensure that a large number would have used birth control pills. They were also primarily white due to the makeup of the nursing population at the time.We sent our first questionnaire to these nurses in 1976. Though fairly straightforward, this questionnaire was actually the product of much deliberation and debate. The questions were designed so that they could be answered relatively easily, while still providing us with enough information to establish scientific relatHankinson, Susan E. is the author of 'Healthy Women, Healthy Lives A Guide to Preventing Disease from the Landmark Nurses' Health Study' with ISBN 9780743217743 and ISBN 0743217748.