The study by British and Australian researchers, published Thursday in the Lancet, suggests the practice of self-harm usually vanishes in late adolescence, often without any mental-health treatment, the Los Angeles Times reported.
But that doesn't mean parents should ignore the behavior, the authors said.
Many youths who indulge in self-harm have underlying mental-health problems such as depression or anxiety that can persist into adulthood, they said.
Youths who practiced self-harm at any time were 3.7 times more likely to have depression or anxiety even though less than 1 percent continue exhibit the behavior past age 29, the study found.
While it may be reassuring to parents to know self-harm often is a temporary behavior, the authors said, they should look closely at their children's overall mental health.
"Our findings suggest that the treatment of such problems might have additional benefits in terms of reducing the suffering and disability associated with self-harm in later years," they wrote.