Adolescence sex comes with health risks later

These findings from a lab animal study, conducted by Ohio State University researchers, could be applied to understanding human sexual development.

"Having a sexual experience during this time point, early in life, is not without consequence," said John Morris, study co-author and doctoral student in psychology at the university.

"It could be affecting males' susceptibility to symptoms of depression, and could also expose males to some increase in inflammation in adulthood," Morris added.

Researchers paired adult female hamsters with male hamsters when the males were 40 days old, the equivalent of a human's mid-adolescence, according to a varsity statement.

Male animals with an early sexual experience showed more signs of depression-like behaviour as well as smaller reproductive tissues and changes to brain cells than did hamsters that were first exposed to sex later in life or to no sex at all.

Among the cellular changes in hamsters with early sex were higher levels of gene expression, tied to brain tissue inflammation and its structures in key signalling areas.

They also showed signs of a stronger immune response to a sensitivity test, suggesting their immune systems were in a heightened state of readiness and could turn on itself.

These findings were presented at the Society for Neuroscience annual meeting in Washington D.C. Morris co-authored the study with Zachary Weil, assistant professor and Randy Nelson, professor and chair, both from the university's Neuroscience department.