New research from the ESRI and the HSE analyses how young people receive information on sex and relationships and their sexual behaviours.
It found that a third of 17 year olds have had sex with almost 90% using contraception.
Nearly a quarter of young people regretted their first time, rising to 31% of young women.
Meanwhile a quarter of boys and 20% of girls said the main source of information about sex was internet, TV, films or books.
Co-author of the report, Associate Professor, Anne Nolan, described the finding as worrying.
"We don't know from the survey what information [17-year-olds] are sourcing from the internet, one suspicion we would have is that pornography is being used here."
The survey asked more specific questions to older age groups.
"There's quite a high use of pornography at the age of twenty and that's concerning in terms of what information they're getting."
She said pornography can provide misinformation about sex and relationships.
(1/8) “Talking about sex and sexual behaviour of young people in Ireland" – new research report launched from the joint ESRI/HSE Health and Wellbeing research programme today @ESRIDublin & @hsehealthw pic.twitter.com/wU2IBHDebC
— HSE Sexual Wellbeing (@_respectprotect) November 10, 2020
Sex Education Focuses On Biology Instead Of Emotional Aspect Of Sex
Most - 92% - of 17 year olds reported that they had received sex education at school, many noted it being a scientific discussion.
Ms Nolan said "There was still a lot of stress on the biological aspects of sex and not enough on how to navigate relationships."
This was echoed by co-author Emer Smyth.
"When asked, young people are critical of it focusing too much on the biology of sex and not enough on the emotional aspect."
School should not be the only source of sexual education, according to Psychotherapist Stella O'Malley.
"Parents are leaving it to schools and I don't think that's responsible," she said.
"It's not just one big talk, it's a lot of small talks."
Ms O'Malley said "The Talk" shouldn't just be about sex.
"Make sure your children know not to send inappropriate texts and know not to receive them."
The research also finds that four in ten 17 year-olds have not spoken to their parents about sex and relationships.
Those that did, were significantly more likely to use contraception.
