Factors affecting the age at menopause

Summary A postal questionnaire was sent out in September 1977 to all women aged between 40 and 60 years in Ede, the Netherlands. The design of the study was similar to that used by Jaszmann et al. in 1967 in the same locality. The response rate was 66·6%. Data were analysed using theprobit analysis, a segmentation analysis and by applying chi-squared tests to cross tabulations. The median age at menopause was 51·7 years, 3 months later than in 1967. When, however, women who were taking oral contraceptives at the time of the survey were excluded the median age at menopause was found to be virtually the same as 10 years previously. The effect of factors associated with early or late menopause was studied. The results are discussed. The concept of a secular trend is briefly commented upon.