The Internet is the most important source of information about sex for Chinese teenagers, as sex education at school and home is inadequate, according to a survey.

More than three-quarters of the survey's 3,000 teenage respondents said the Internet is their most important source of information about sex. Books and friends were the next most important sources of knowledge about sex. School and parents ranked as the two least important sources.

The China Youth Daily newspaper conducted the survey.

"There is a severe lack of formal sex education in China, so many teenagers turn to the Internet," says Ye Qing, a post graduate student at the Second Military Medical University who runs an online sex education forum for Chinese youth.

Still, 71 percent of the respondents believe obscene content on the Internet disturbs teenagers.

"We do have sex education in the school. But it is far from enough," says Zhang Chao, an Internet celebrity for his sex lectures stuffed with jokes.

Some 12 percent of the survey's respondents believe sex education for children under the age of 10 is appropriate, even as 42.5 percent said primary school students already have some awareness of sex.

Children and college students should be provided with sex education, says Zhang Meimei, director of the Sex Education and Research Center at Beijing Normal University.

Pan Suiming, head of the Institute for Research on Sexuality and Gender at Renmin University of China, stresses that sex education must be compulsory. He also suggests a changes in how sex education is provided.

"We should not focus on what we can tell teenagers. We should focus on what they want to know," Pan says.