Figure 3.

Sex-specific hormone levels during reproductive age and in aged individuals. With aging, women experience an abrupt reduction in estrogen and progesterone levels as ovaries cease to produce these steroids at menopause around their 45–55th year of age (Davison et al., 2005; Laughlin et al., 2000; Santoro et al., 1996). In males, the decline in total testosterone levels occurs progressively, with no distinct time-point of andropause (Bhasin et al., 2011; Jasuja et al., 2013; Tancredi et al., 2005). Mean glucocorticoid levels of both men and women increase linear (Van Cauter et al., 1996), while morning cortisol levels are higher in aged women than in age-matched men.