The Million Women Study
The Million Women Study is one of the largest prospective studies of women’s health in the world. Over 1.3 million UK women were recruited into the study between 1996 and 2001 and have been followed for health outcomes ever since.
The study was initially set up to provide reliable information on the risks associated with different types of menopausal hormone therapy but was designed to be able to provide information on the effects of many other factors that could affect women’s health as they age.
Most of the women who joined the study reached adulthood in the 1960s and had considerably different lifestyles to those of previous generations. For example, many had begun smoking and using oral contraceptives as teenagers and young adults. The prevalence of obesity was also increasing, and there were claims that other behaviours, such as diet, were likely to have important effects on health. For this reason, the study provides unique insights into the effects of many of these factors on health.
The Million Women Study is coordinated by a team of researchers in the Cancer Epidemiology Unit and led by the Principal Investigators, Professor Gillian Reeves and Associate Professor Sarah Floud. To date, some of the most important findings from the study have been on the association of menopausal hormone therapy use with the risk of female cancers, the effect of lifelong smoking on women’s health, and the burden to health associated with overweight and obesity.
The study has published many important research papers, and its value as a resource for health-related research is likely to increase as the cohort matures and other health conditions become increasingly common.
The study is currently investigating the effects of behavioural and other risk factors on women’s risk of developing or dying from different types of cancer, heart disease, stroke, dementia and other mental and neurodegenerative disorders.
We are indebted to the 1.3 million women who have given their time and energy to fill in questionnaires about their health.