OBJECTIVE: To assess the risk of onset of menopausal symptoms at different periods surrounding menopause, and variations in this risk according to age at menopause and type of menopause. METHODS: We analyzed the 27,897 women participating in the French E3N cohort study who reached menopause during a 10-year follow-up period (1990-2000). Self-administered questionnaires, completed approximately every 24 months, included questions on the use of hormonal treatments, reproductive factors, personal history of a variety of diseases and the occurrence of personal medical events, including menopausal symptoms. Hazard ratios (HRs) were computed from multivariate Cox models. RESULTS: When compared to the year preceding menopause, the risk of onset of menopausal symptoms was higher in the year following menopause (for natural menopause (n=25,753), HR=1.22, 95% confidence interval: 1.17, 1.27, and for artificial menopause (n=2,147), HR=2.21, 95% CI: 1.93, 2.52). More than one year prior to menopause and more than one year after, HRs were significantly below unity. The risk of onset of menopausal symptoms in the year following menopause was 1.47-fold (95% CI: 1.31, 1.64) higher in women having undergone an artificial menopause than in women who had had a natural menopause. In other periods, the risks did not differ significantly according to type of menopause. Those who experienced menopausal symptoms in the 1-5 year period following menopause were more likely to have reached their menopause before 51 years. CONCLUSIONS: The risk of onset of menopausal symptoms at different time periods surrounding menopause varies according to both type of menopause and age at menopause.