Stress - not only the environmental type associated with earthquakes, but also marital or job stress - was likely to affect the placental clock and shorten gestation, she said.
Longevity genes appear to slow down the aging process by making cells and tissues more stress-resistant, better able to withstand the inevitable environmental insults that accumulate over a lifetime from bad diet, inflammation, radiation, genetic mutations and toxic chemical by-products called free radicals.
Evidence of oxidative stress can appear under other conditions, including exposure to certain environmental pollutants or infections in the urinary genital tract.