ABSTRACT
To study the pattern of age at menopause in Semnan Province, Iran. A total 3545 women, 30 years or older, were selected using a cluster random sampling method and interviewed to fill out a questionnaire. Since the object of the study was determination of the pattern of age at natural menopause, some cases with abnormal, operative and so on, ignored and finally 3404 women were enrolled in the study and the pattern of the age at menopause was estimated using prevalence of menopause in each age group. The total mean and median of age at natural menopause were 52.40 5.02 and 50.40, respectively. Increasing of menopause was slow from age 30 to 43, but its speed increased until 55 years old, then decreased slowly. compared to the other regions of Iran, the mean of age at natural menopause in Semnan seems higher