Choosing Not to Reproduce May Extend Lifespans Across Mammals, New Study Finds

A mega-analysis of 117 mammal species shows that restricting reproduction—via contraception or sterilization—can extend life expectancy by about 10%, with male lifespans increasing when testosterone is reduced through castration (vasectomy effects vary), and females living longer when reproduction is blocked. The results point to energetic and hormonal costs of reproduction as a trade-off with survival, though effects vary by species and context, and human implications remain uncertain.