A longitudinal population study of 1462 women initially aged 38-60 has been proceeding in Gothenburg, Sweden since 1968. The results presented in this paper deal with menopausal age in relation to cardiovascular disease and overall mortality and refer to the initial 12-year follow-up period. The risk ratios concerning early menopausal age for all the various cardiovascular end-points studied were increased, except for new events of ECG changes suggestive of ischaemic heart disease. However, none of the risk ratios studied between menopausal age on the one hand and the 12-year incidences of myocardial infarction, angina pectoris, or stroke, on the other, was significantly increased when women who had reached the menopause at the age of 40, 45, or 50 were compared with the rest of the participants in the population study. When early menopause was related to the overall mortality, the risk ratio was increased only for women who had reached the menopause at the age of 50, but not sufficiently to be statistically significant. When reviewing the literature, it is obvious that the results from previous studies are discrepant and do not permit of any generalized conclusion as to whether there is a correlation between early menopause and ischaemic heart disease or not. Nor is our longitudinal study conclusive in this respect.