One in 20 university students has had, or caused, an unintentional pregnancy, a new study of the sexual behaviour of students has found.
The study found condom use was uncommon, even though having multiple sexual partners was common, leading researchers to raise concerns about the number of students at risk of sexually transmitted infections and unintended pregnancies.
Nearly 3000 17- to 26-year-old students from across New Zealand took part in the study by Rebecca Psutka, Kimberly Cousins and Prof Jennie Connor, from the University of Otago's department of preventive and social medicine, and Associate Prof Kypros Kypri, from the University of Newcastle's School of Medicine and Public Health.
The results of the study are published in the New Zealand Medical Journal today.
The researchers said their aim was to describe the sexual health and behaviour of university students as a sentinel population of young New Zealanders - something on which there was previously little information.
They were also motivated by increased concern about the potential impact of high or risky levels of alcohol consumption on resulting sexual behaviour.
The study found one in five respondents had three or more sex partners in the past year. It found 26 per cent said they last had sex with someone they had just met, and had not used a condom.
Only 54 per cent of the respondents used a condom when they last had sex, a lower rate than in a 2000 study of high school pupils, which found 63 per cent of that younger age group used a condom in their last sexual encounter.
A high rate of termination was also revealed.
In the study group, 3 per cent-4 per cent of 17- to 19-year-old women and 6 per cent of women overall had an unintentional pregnancy, with 74 per cent of the pregnancies terminated, compared with a similar Australian study which found 1.7 per cent of 16- to 19-year-old women got pregnant unintentionally and 18.9 per cent of those pregnancies were terminated.
New Zealand's high rates of chlamydia and teenage pregnancies indicated a sub-optimal use of effective contraception, even though there were few barriers to students getting condoms, which were heavily subsidised and widely available.
"This study suggests that ease of access is not sufficient to ensure appropriate use."
Efforts clearly needed to continue to promote condom use among young people, the researchers concluded.
More investigation of the reasons for not using condoms could help.
The researchers acknowledged that the subject group might not necessarily be indicative of all young people, as the evidence was university students drank more heavily than their non-student peers.
A 2005 survey found university students often attributed unsafe, unhappy and unwanted sexual experiences to drinking.
While there was some research that suggested alcohol was often involved when students made risky choices, a better understanding of how drinking affected sexual behaviour and led to not using condoms would be useful to develop intervention strategies.