London, Nov 10 (IANS): The surge in online communication and social media coupled with economic downturn seven years ago have left many teenage girls with low self-esteem, reveals a British survey.

The survey that included 30,000 students found a worrying drop in the number of 14- and 15-year-olds, particularly girls, who say they feel highly confident in their own worth, the Guardian reported.

"In 2007, 41 percent of 14- and 15-year-old girls reported high self-esteem. This has fallen to 33 percent now," the findings from the Schools Health Education Unit showed.

For boys, the low self-esteem figure came down to 50 percent from 55 percent in 2007.

"Three in four 14- and 15-year-old girls have chatted on the internet and 13 percent received a message that scared or upset them."

One in five girls had chatted with people they did not know.

A third of all pupils looked online for pornographic or violent images, films or games.

Researchers warned that teenagers were having their lives exposed through online communication and schools should examine this seriously.