The survey lasted for three years, covering 22,712 students in two Zhejiang universities, the largest of its kind in the world. It will be used as scientific evidence for AIDS education in colleges, the Oriental Morning Post reported.

Among the sample, 17.6 percent of male students have had sex compared to 8.6 percent for female students.

The percentage that have had sex is highest in physical education institutes at 36.3 percent, and art design students posted the second highest with 24.9 percent, followed by computer science, biology and environment, information technology, and culture and communication students.

Among those who have had sexual experience, 27.4 percent of students have at least two sex partners. The survey reported that 34.2 percent of experienced female students said they were reluctant their first time, and 2.6 percent of them even said that they were forced to have sex.

The survey said those who often dance, sing in karaoke, smoke or drink are more easily to have sex. Smoking students have sex at the average age of 18.94¡À1.7, one year earlier than those who don't smoke.

The survey shows more than half of college students agree with having sex before marriage and can have sex if they love each other.

About 12 to 18 percent of students agree that people can have sex with others even if they already have a boyfriend or girlfriend. They also agree with having sex with others for money and having homosexual activity.

Among those experienced students, 2.44 percent of male students have had homosexual activity and 2.57 percent of female students have had such behavior, the survey said.

But these students lack sex education, as 70 percent of them said it's impossible to contract AIDS or venereal diseases through sex, while only 15.96 percent of them use a condom every time.

They use condoms to avoid pregnancy rather than prevent disease, the survey said.

"AIDS and venereal diseases can be spread among college students," said a member of the survey group. "Pregnancy, abortion, AIDS and venereal disease may become important problems in universities in the future if not controlled."