Hidden, undetected and poorly researched, deliberate self-harm - including cutting, hitting and burning - is a damaging coping mechanism that an estimated 17 per cent of girls and 12 per cent of boys have resorted to by the end of their teenage years.
For those aged 15 to 24, one in eight report having self-harmed, according to headspace, the Federal Government's youth mental health foundation.
While the behaviour can range from mild scratches to "a worrying escalation in lethality", headspace reports it is a response to emotional pain rather than an attempt to end their life.
One of the first to publicly admit to the problem, British Olympic cycling gold-medallist Victoria Pendleton this month revealed in a newspaper the stress of success had triggered past episodes of cutting.
The few studies that have been conducted locally estimate the number of young people who have self-harmed is 40 to 100 times greater than those who have actually ended their lives, with possibly as many as 200,000 self-injuries across all ages in Australia each month.
Frequency can range from only once to 50 times a month and it's been estimated, based on community surveys, that while most tell a friend, only a third seek help and 10 per cent seek medical treatment.
Headspace's clinical manager Vikki Ryall said it was unhelpful to say there was an "epidemic" of self harm or label it a "trend" because data collection was insufficient and unable to determine how often it occurred or reveal any increase.
However, those in the mental health field had recently come to realise self-harm was "much more common than previously thought". And while the community was just now beginning to talk more openly about it, there was still significant under-reporting.
WA psychiatrist Julia Charkey-Papp, who specialises in adolescent care, said she understood WA schools were currently dealing with a lot of self-harm behaviour among students.
She said self-harm was a problem that tended to fluctuate over time, with increased awareness about it in general making it less of a taboo.
What is ringing alarm bells in schools is that it can spread among friends who may also be fragile or depressed.
They may try it out as a way of showing pain they are too immature to have the emotional vocabulary to express. Most commonly it starts when people are aged about 12 to 14 years old.
Recorded throughout history, self- harm is not considered to be a mental disorder or illness, but a symptom of distress.
However, this is under review, with non-suicidal self-injury proposed as a new diagnosis for inclusion in the revision next year of the mental health field's international manual - the Diagnostic and Statistical Manual of Mental Disorders produced by the American Psychiatric Association.
"Regardless of whether it is increasing or not, it is certainly a problem," Ms Ryall said. "Although self-harm is relatively common in young people, we need to avoid thinking that it is normal behaviour."
If asked to guess at what might be driving this, Ms Ryall said one contributing factor might be that Australia's young, with brains and emotions still developing, were reaching puberty earlier and the process of individualisation earlier, and were then turning to inexperienced peers to help them cope with complex problems.