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KEY DATA 2021

Sexual health and identity

Presenting data on young people’s sexual behaviour and how they identify.  Sections include what age young people start to have sexual relationships; contraception use; conception and birth rates for young parents; and sexually transmitted diseases.

In England, Wales and Scotland the under 18 conception rate has continued to fall since the 1990s

Sexually transmitted infections

As well as pregnancy, sexual behaviour carries the possibility of sexually transmitted infections (STIs). Public Health England data on the number of STI diagnoses in England make it clear that the highest rates of infection in heterosexuals are among those aged 15-24. Indeed, it is estimated that those under 25 accounted for 59% of all new chlamydia cases in 2019 (Public Health England, 2020a), as well as significant proportions of other STIs as well.

Chart 3.13 demonstrates that the 20-24 age group is most at risk of STIs for both genders, and that rates are highest in young women of this age. Helping all young people to protect themselves is a major public health issue, but the higher rates in young women indicate that particular attention needs to be paid to health promotion strategies targeted directly at them.

Young women 20-24 are at most risk of a new STI diagnosis

Chart 3.14 presents the rates of selected STI diagnoses, per 100,000 population, for young people in England in 2019 by gender and age. Chlamydia is clearly the most frequent STI diagnosis, followed by genital warts and gonorrhoea. Cases of syphillis are rare. 

Chlamydia is the most frequent STI diagnosed in young people

Improvements in screening and diagnosis have meant that more STI cases are identified now than previously, so untangling the underlying trend is complicated. England’s National Chlamydia Screening Programme, launched in 2003, has diagnosed well over half a million infections in 15-24 year olds, increasing its visibility in the statistics. On the other hand, rates of anogenital wart diagnoses in 15-24 year olds have been in decline over the last five years (Public Health England, 2020a).

The introduction of the HPV (human papilloma virus) vaccination in adolescent girls through the National HPV Vaccination programme may potentially have an impact on recent trends in a new diagnosis of genital warts. Rates fell during the 2019/20 year, presumably because of the impact of school closures during the Covid-19 pandemic. From September 2019, boys have been offered the HPV vaccine free in schools from age 11 to 13 in Scotland, and age 12 to 13 in the rest of UK. 

Most of the data in this section have related to England, but sexually transmitted infections in young people in other countries of the UK show a similar pattern, although Scotland and Wales do not have organised screening programmes. In Scotland in 2018, available data suggest that two thirds of all chlamydia diagnoses were made in people under 25 (54% of male and 74% of female diagnoses in this age group respectively). The majority of these diagnoses were in those aged 20-24. (Health Protection Scotland, 2019).

Finally, in 2019 there were 395 new HIV diagnoses among those aged 15-24 years in the UK, which represents a fall of 54.4% over the previous 5 years since 2014. In addition, 285 children under-15 were receiving care for diagnosed HIV infection, together with 2,313 young people aged 15-24 (Public Health England, 2020c).

All data correct as of 1st November 2021

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