Reproductive Tissues Influence Life Span
A review paper: "Aging and reproduction are two defining features of our life. Historically, research has focused on the well-documented decline in reproductive capacity that accompanies old age, especially with increasing maternal age in humans. However, recent experiments in model organisms such as worms, flies and mice have shown that a dialogue in the opposite direction may be widely prevalent, and that signals from reproductive tissues have a significant effect on the rate of aging of organisms. This pathway has been described in considerable detail in the nematode Caenorhabditis elegans. Molecular genetic studies suggest that signals from the germline control a network of transcriptional regulators that function in the intestine to influence longevity. This network includes conserved, longevity-promoting Forkhead Box (FOX)-family transcription factors such as DAF-16/FOXO and PHA-4/FOXA, nuclear hormone receptors (NHRs) as well as a transcription elongation factor, TCER-1/TCERG1. Genomic and targeted molecular analyses have revealed that these transcription factors modulate autophagy, lipid metabolism and possibly other cellular processes to increase the length of the animal's life."
This makes sense on one level, and I would like it to be true, but there is no plausible mechanism provided to explain how the signaling patways know that one has reproduced.