Young people in Shanghai are having their first sexual activity earlier than older generations, and more choose cohabitation before marriage, according to a report issued yesterday by the Shanghai Academy of Social Sciences.

People born in the 1980s have sex for the first time at an average age of 21, said the report based on the questionnaires of 2,200 locals born from the 1950s to the 1980s. The average is the same for men and women.

In comparison, men and women born in the 1970s had their first sex at an average age of 23, while the average age for people born in the 1960s or 1950s was 25 for men and 23 for women.

Meanwhile, about 45 percent of married people born in the 1980s live together before marriage, compared with 30 percent for people born in the 1970s and 15 percent among those born in the 1960s and 1950s.

"More kids experience early puberty now," said Zhou Haiwang, deputy director of the academy's population and development studies. "Children also have easier access to sex information from novels and websites, compared with the previous generations," he said.

He advised local schools to introduce sex education to students earlier, including in primary schools. Many schools now wait until students are in middle school before giving them sex education.

"Children should know the hazards of unprotected sex and abortion," Zhou said.

The study found about half of people born in the 1980s have never had sex. "This reflects many young people are not as open as the prevailing thoughts about them," Zhou said.

Another part of the report noted that older people have poorer awareness of safe sex than young people. Nearly half of all respondents seldom use condoms, particularly migrants.

About 63.8 percent of people born in the 1950s and 1960s have never used condoms. But that proportion drops sharply with younger generations. The percentage is 39.8 percent for people born in the 1970s and 25.6 percent for those born in the 1980s.

Most local couples said they were satisfied with their sex lives, according to the report. About 72 percent of people in marriage or living together said their sex life is "very harmonious" or "harmonious." Only 3 percent said it was "disharmonious" or "very disharmonious" and the remainder choose "mediocre."