The Digester

Fecal transplants from old mice boost fertility in younger mice

Mar 3rd 2026

A Nature Aging study found transferring gut microbiota from older female mice to younger females improved ovarian markers and fertility in mice, a surprising and preliminary result that will need more research before any human implications can be drawn.

  • Young female mice given fecal transplants from older, nonovulating females showed rejuvenated ovarian gene markers and higher reproductive success.
  • The donors were in estropause, a mouse stage similar to human menopause, and had stopped ovulating.
  • Researchers propose changes in the estrobolome, a gut microbe group that interacts with the ovaries, may restore gut-ovary signaling but the exact mechanism is not proven.
  • The study published in Nature Aging is preliminary and not directly applicable to humans, and more work is needed to identify responsible microbes, confirm causality, and assess safety.