Nearly 90 percent of young couples surveyed in Tokyo say they are dissatisfied with the sex education they receive at school and elsewhere, and feel adults should not hesitate to teach them how to avoid contracting sexually transmitted diseases, according to a health ministry study.

The survey, made available Sunday to Kyodo News, shows 87.2 percent of the respondents become impatient with adults who are embarrassed to talk about sex, while 62.6 percent said they think it is ridiculous that adults believe junior high and high school students do not have sex.

It also showed 77.1 percent of female respondents, all in their teens, have had sex.