An investigation of the age at menopause.

Data from a representative sample of 736 women aged 45–54 living in or near London in 1965 were analysed with respect to menopausal status and median and mean age at menopause (final menses). The median age at the natural menopause was 50·78 years. The validity of the measures used and the reliability of the data in this and previous studies are discussed. The conclusions are reached that median age of menopause is a more valid measurement than mean age and that there is no conclusive evidence of an increase in the age at menopause over the last century. The data also indicate understatement of the age at the last menstrual period (LMP) by women, with increasing lapse of time.The menopause was found to occur markedly later in currently married women than in unmarried or previously married women. When marital status was controlled by considering currently married women only, increased parity was shown to be related to a late menopause among women of higher socio-economic status, but not among those of lower socio-economic status. There was no notable association between the menopause and early or late menarche and socio-economic status. [ABSTRACT FROM PUBLISHER]