Low digit ratio (2D:4D) is associated with early natural menopause

Intrauterine environmental conditions may affect the number of primordial follicles and in this way the timing of menopause. The aim of the present study was to investigate association patterns between right hand digit ratio, that is, 2D:4D - as an indicator of prenatal androgen and estrogen exposure, and age at menopause.

One hundred sixty-nine women, who had experienced natural menopause, were enrolled in the study. Length of second and fourth finger were measured directly from the palmar side and digit ratios of both hands were calculated. For further analyses the digit ratio of the right hand was used only. Additionally, smoking habits, body weight and body height, body mass index and the number of children were determined. Multiple regression analyses were used to test association patterns between digit ratio and age at menopause, body height, BMI, nicotine consumption as well as number of births and age at menopause.

Age at menopause correlated significantly positively with the digit ratio. A more feminine digit ratio is associated with a higher age at menopause, while a low digit ratio, interpreted as a hint of a higher androgen exposure during prenatal phase was associated with a lower age at menopause.

Low digit ratio is associated with an earlier onset of natural menopause.