Postponement of postmenopausal mortality acceleration in low-mortality populations.

Mortality analyses commonly disregard postmenopausal acceleration. This study examined period log mortality in World Health Organization (WHO) data for 34 low-mortality countries in 2000, demonstrating significant gradient increases for women (33/34 countries) and men (22/34), from a later age than previously reported, dividing the postmenopausal period into phases. "Break points" were identified as intersects of lines of best fit to these and the same approach was used in analysis of Human Mortality Database data for 19 countries. There has been an upward migration of about 10 years in female age at break point since 1850. Male data flipped from mortality acceleration to deceleration and back in the late 20th century with no apparent shift in break point. Altered age at mortality acceleration appears genuine, gender-specific, and internationally consistent. Its timing prompts the hypothesis that it may relate to falling fertility.