Published in the Journal of Adolescent Health, the study describes changes in young people's sexual practices using nationally-representative data from the National Surveys of Sexual Attitudes and Lifestyles (Natsal¹), the largest scientific studies of sexual health and lifestyles in Britain.

Conducted by the London School of Hygiene & Tropical Medicine, UCL and NatCen Social Research, the three studies have been carried out every 10 years since 1990, and have involved interviews with more than 45,000 people to date.

Whilst vaginal intercourse and oral sex remained the most common combination of sexual practices experienced in the past year, the proportion of sexually active 16-24 year olds who said they have had vaginal, oral and anal sex during the last year has risen, from approximately one in ten women and men in 1990-1991, to one in four men and one in five women in 2010-2012. Some of the largest increases in the prevalence of oral and anal sex over the past decade were observed among those aged 16-18.

Lead author Dr Ruth Lewis, who conducted the work while at the London School of Hygiene & Tropical Medicine but is now based at the MRC/CSO Social and Public Health Sciences Unit, University of Glasgow, said: "At a time when much sex and relationships education is being updated, keeping pace with current trends in sexual practices is crucial so that curricula are tailored to the realities of young people's experiences.

"By shedding light on when some young people are having sex and what kinds of sex they are having, our study highlights the need for accurate sex and relationships education that provides opportunities to discuss consent and safety in relation to a range of sexual practices. This will equip young people with the information and skills they need to maximise their wellbeing from the outset of their sexual lives."

Kaye Wellings, senior author and Professor of Sexual and Reproductive Health at the London School of Hygiene & Tropical Medicine, said: "The changes in practices we see here are consistent with the widening of other aspects of young people's sexual experience, and are perhaps not surprising given the rapidly changing social context and the ever-increasing number of influences on sexual behaviour. It is important to keep up to date with trends in sexual lifestyles to help young people safeguard their health and increase their well being."

While many studies focus on age at first sexual intercourse, less is known about when people start having sexual experiences of any kind, including kissing2. The researchers found that median age at first heterosexual experience has not changed much in recent decades. In the most recent survey, the median age of reported first heterosexual experience among men and women born between 1990 and 1996 was 14. The median age at first intercourse (oral, vaginal or anal) among this group was 16.

The researchers acknowledge that, as with most surveys, their study is limited by the self-reporting of behaviour, which may be influenced by prevailing social norms. The authors also state that the number reporting same-sex experience was not sufficient to extend their analysis to practices between same-sex partners.

###

Natsal was funded by the Medical Research Council and the Wellcome Trust, with additional funding from the Economic and Social Research Council and Department of Health.