Having sex as a teenager can have lasting negative effects on the body and mood into adulthood, a new study with lab animals suggests.
Researchers at Ohio State University paired adult female hamsters with male hamsters when the males were 40 days old — the equivalent of mid-adolesence in humans. When compared to male hamsters who were not exposed to sex early in life, the males who had an early-life sexual experience showed more signs of depressive behaviours as well as lower body mass, smaller reproductive tissues and changes to cells in the brain.
The animals who had sex as adolescents had higher levels of a gene associated with inflammation in their brain tissue, and showed signs of a stronger immune response to a sensitivity test.
These effects are not harmful, but researchers say they suggest that sexual activity during the nervous system’s development might be interpreted by the body as a stressor.
“There is a time in nervous system development when things are changing very rapidly, and part of those changes are preparations for adult reproductive behaviours and physiology,” study co-author Zachary Weil said. “There is a possibility that environmental experiences and signals could have amplified effects if they occur before the nervous system has settled down into adulthood.”
Although the study used lab animals, researchers say the findings provide information that may apply to human sexual development.