Introduction

Sexual health becomes a new health priority in early adolescence. The sexual health of young people is a matter of intense public concern. The adverse consequences of unsafe sexual behaviour—such as pregnancy and sexually transmitted infections (STIs), including HIV infection—affect adolescents as well as adults. “Risk taking” behaviours are common when adolescents start being sexually intimate and are often linked with other health risk behaviours, such as substance misuse.

Relationships and sexual behaviour

The median age for first sexual intercourse in the United Kingdom dropped during the early 1990s and is now stable at around 16 years for both men and women. The disparity between the sexes observed in the early 1990s has diminished. Before the age of 15, about 18% of boys and 15% of girls report having had full sexual intercourse, with similar proportions having engaged in oral sex.

Having sex for the first time at an early age is often associated with unsafe sex, in part through lack of knowledge, lack of access to contraception, lack of skills and self efficacy to negotiate contraception, having sex while drunk or stoned, or inadequate self efficacy to resist pressure.

About 10% of boys in the United Kingdom report that they were drunk or stoned when they first had sex, and 11% of girls report being pressurised by their partner when they first had sex. Of those under 16 years who have ever had sex, about a third to a half of both sexes report ever having had unsafe sex.

Sexually transmitted infections

Considerable rises in the incidence of STIs, particularly chlamydia, have led to a major public health problem in the United Kingdom. Although rates in the under 16s have …