Teenagers are under pressure to send nude photos of themselves and other sexual images from their mobile phones as "sexting" becomes more widespread, new Australian research shows.

Melbourne University researcher Shelley Walker said her study showed that young people felt they needed to "sext" to fit in because it had become a "behaviour that has become more normalised in their world".

"It's not a surprise that talk about and experience pressure from boys. There's a pressure that girls experience from boyfriends mainly but also from boys they don't necessarily know," Walker told AFP on Friday.

"Then there's the pressure that young men talked about -- the pressure to be sending images out, to have the images on their phone.

"A couple of guys talked about being called 'gay' (for not having images on their phones)."

Walker, who discussed her preliminary findings at the Australasian Conference in Canberra, said sexting typically occurred when a boy asked his girlfriend for a nude photo of herself.

But it included a range of behaviour including a boy sending a girlfriend an image of his penis and videos of sexual acts.

Walker said young people discussed their friends holding onto these images for blackmail or posting them on social networking site or publishing them on publicly viewed websites.

Walker interviewed 15 males and 18 females aged 15 to 20 for her research and found they all felt a highly sexualised media culture was bombarding them with sexual images, creating a pressure to engage in sexting.

She said the phenomenon had become a focus of much media reporting, but there was little research engaging the views of teenagers on the issue, in a country in which 90 percent of aged 15 to 17 own a mobile phone.

"Our study reveals how complex and ever-changing the phenomenon of 'sexting' is and that continued meaningful dialogue is needed to address and prevent the of 'sexting' for young people," she said.

(c) 2011 AFP