The Medical Research Council's National Survey of Health and Development (MRCNSHD) is a prospective cohort study of 2547 women and 2815 men, a sample of all the births that took place in England, Scotland and Wales between 3-9 March 1946. It is one of the longest running large-scale studies of human development in the world, aiming to identify lifetime biological, social and psychological pathways to health and disease, from early life to ageing. A special study of women's health in midlife and the menopausal transition in this cohort was undertaken by sending to women study members eight annual postal questionnaires from when they were 47 to when they were 54 years old. The findings from the women's health study so far have highlighted associations between multiple risk factors at each life stage, and women's health and disease in later life. The authors suggest that a life course approach may provide a better understanding of women's health during the middle years of life than an approach which restricts itself to contemporary social or hormonal experiences. Of particular interest are their results linking ovarian ageing to developmental factors. Replication of these findings in other life course cohorts is being sought.