A recent survey of 2,700 secondary school students found that the number of them engaging in "sexting", or sending explicit messages, photos or videos to another person, had doubled from a year ago.

It showed that 4.2 per cent of upper secondary students and 1.9 per cent of lower secondary students had posted or sent such risque content via their mobile phones.

We know that Singaporeans sext - a McAfee survey last year had nearly half of the 350 adult respondents admitting to sending or receiving intimate content on their devices - but the fact that more youngsters are doing it has raised eyebrows.

Unlike adults, teenagers do not have the emotional and social maturity needed to navigate the power dynamics within relationships that sexting often feeds on.

So while sexting appeals because it adds titillation and stealth to relationships, it could easily morph into something more sinister.

Some boys, for instance, may circulate the materials in class to secure bragging rights while others use them to blackmail their partners.

When things turn sour, spurned lovers may also vindictively publicise once-intimate content.

The emotional distress from having such materials appear in the public sphere could be as damaging as them taking their lives, as seen in the cases of some United States teenage sexting victims.

The other risk is that, according to research, offline behaviour mimics that online and underage sex follows. A study in the journal, Pediatrics, last year found that teens who sext are more likely to become sexually active a year later.

So what can we do? The authorities here could follow their Canadian counterparts, who tweaked the sex education curriculum this year to include the dangers of sexting.

Parents could also install nanny filters on the smart devices like they do for family desktops. Such software will send the parent any photo the teen takes before it can take flight.