"Current strategies are not working to improve access to contraception for young people, especially among our poorer communities," said study author Dr Terryann Clark, of the University of Auckland's School of Nursing. "There are also significant cultural and access issues for Maori and Pasifika youth."
Youth development literature suggested one of the best ways to reduce teen pregnancy was by making sure young people were engaged in school and had goals for the future.
"In that case they are far less likely to get pregnant, so strategies that address youth sexual health must take into account the big picture - education, employment and aspirations," said Dr Clark.
Another strategy was ensuring young people could access free, non-judgmental and culturally responsive sexual healthcare and information.
Dr Clark believed health professionals, educators and families did not address sexual health issues well, and the topic was "shrouded in secrecy, shame and embarrassment".
"Society still finds youth sexual behaviour difficult to talk about, and therefore resources ... are limited."
A comprehensive approach to sexual health was required if New Zealand wanted healthy young people who felt valued and contributed well to society, she said.
The first phase of a national sexual and reproductive health strategy was introduced in the early 2000s, but there had been no update since.
"I do think it's because it's a politically and socially challenging area, and people tend to shy away from it," Dr Clark said.
Health Minister Jonathan Coleman could not be reached for comment yesterday, but New Zealand Family Planning agreed new strategies were needed to target at-risk young people.
The organisation's chief executive, Jackie Edmond, has written to the Government highlighting a decade-long, cross-ministry programme in the UK that slashed teen pregnancy rates to record lows.
Such an approach was needed in New Zealand, where sexual education remained ad-hoc, she said.
Efforts were being made by organisations including youth groups, agencies such as the New Zealand Sexual Health Society and schools themselves.
Secondary Principals' Association of New Zealand principal Sandy Pasley acknowledged there was a problem, but added that what was being delivered in schools must be making a difference, given the rise in young people opting to delay sex.
For principals, addressing the issue could be complicated and what information was received by each pupil depended on parents.
"It's tricky, because schools have the obligation to consult with parents and the community on the delivery of courses about personal health and wellbeing, and they have the right to withdraw their children from classes."
The study is published in the Australian/NZ Journal of Public Health.
By the numbers
• The study found that among secondary students surveyed in 2001 and in 2012, there was a near 7 per cent drop in those who had "ever had sex" and a 2.3 per cent decrease in those who reported being sexually active at the time.
• But there was also a decline in those reporting they always used condoms (down 3.3 per cent), used condoms the last time they had sex (7 per cent) or "used contraception at last sex" (5.8 per cent).
• Rates of teen pregnancy and abortion were declining. 18.8 per cent of teenagers in Kiwi secondary schools were sexually active in the 2012 figures.
