Experimentally induced stress decreases ideal female reproductive timing.

Previous correlational research shows that childhood adversity is associated with earlier age of reproduction in humans and other species. Such studies, however, cannot show that stressful conditions cause earlier reproduction. Using the cold-pressor task, we built on previous work to test the idea that acute stress influences human reproductive and marital ideals, and that individual stress responses depend on adaptive life history strategies shaped by exposure to adversity during childhood. Acute stress shifted ideal ages of first birth and marriage to earlier ages. We also tested a competing hypothesis, whether stress had a more general impact on time preference, but found no evidence that it did. Furthermore, there was an interaction between childhood adversity and acute stress. Individuals who reported more exposure to childhood adversity responded to acute stress by reporting even earlier reproductive ideals. These findings offer experimental evidence that physiological stress can alter reproductive decision making in humans.