Sydney - The prime cause of teenage girls seeking treatment at Australian hospitals is not for injuries sustained accidentally but those inflicted deliberately by the girls themselves.

New research from the Australian Institute for Health and Welfare shows that the rate of self-harm among girls aged 13 to 19 has risen by a third since 2000. Three times as many girls as boys are being admitted for slashed limbs or other self-inflicted injuries.

Self-harm is an international phenomenon in western societies and all sorts of reasons are adduced for it. Psychologists say it's a call for help, the response to which is usually the individual instantly becoming the centre of attention.

But not always. Girls often harm themselves on parts of their bodies that family and friends don't see. It's a surreptitious activity and a demonstration of power over something they can control.

Bruce Tonge, from Melbourne's Monash University, said that pressure to do well at school was undermining self-esteem. There was also the loss of family rituals like having meals together and watching television together.

"There may be some alienation within families," Tonge said, noting that self-harm was a "cry for help, a communication where other communications have failed."

It's also sometimes a communal activity with schoolgirls engaging in copy-cat, self-harm activity. (dpa)