Human lifespan and female fertility are moving up at the exact same pace, like they’re both set to the same internal clock.
SocArXiv · March 18, 2026 · b7shw_v1
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The Takeaway
For the last 35 years, the postponement of death and the postponement of childbearing have moved at an identical pace across diverse populations. This implies that the physiological constraints governing menopause and those governing overall longevity are the same, suggesting that human lifespan limits can be calculated by looking at the known limits of fertility.
From the abstract
As births and deaths occur at progressively older ages, further delays must increasingly encounter resistance from existing physiological constraints. For female fertility, these constraints ultimately manifest as menopause. Whether an analogous limit exists for survival, however, remains debated. Evidence indicates that reproductive and actuarial ageing share underlying physiological constraints. We hypothesize that these common constraints limit fertility and mortality postponement in similar