Differences in the age at natural menopause were examined using a retrospective population sample of 289 naturally menopausal women. The mean age at natural menopause was 46.70 +/- 5.44 years. Earlier menopause occurred in women living in semiurban areas, divorced/separated and less educated women, and women who were younger at: first marriage, widowhood, divorce/separation and first or last full-term pregnancy. Later menopause occurred in women who had: irregular menstrual periods before 25 years, dysmenorrhoea and mid-cycle spotting. Duration of oral contraceptives use, weight and body mass index were significantly positively correlated with age at natural menopause. Multiple regression analyses indicated that age at last full-term pregnancy, residence, pattern of menstrual cessation and duration of oral contraceptive use were the significant predictors of the end of menstrual activity.