adolescent couple
Young adults today are having less sex than the generation before them did a few decades ago iStock

Millennials (also known as Generation Y) are less sexually active than their parents were at the same age, scientists have discovered. Young people today are less likely than Generation X to have had sex in their early 20s.

Much has been said about the behaviours, social interactions and personality traits of millennials − the individuals who reached adulthood in the early 2000s.

In particular, when it comes to sex, many studies have described the prevalence of a 'hook-up culture', pointing to the easy access to partners thanks to online dating.

It is thus generally assumed that Generation X – who were born in the 60s and 70s – had less sexual encounters as young adults.

However, a recent study, published in Archives of Sexual Behavior, contradicts this view. It reveals that people aged 18 and over are actually less likely to have sex now than two decades ago, with many factors potentially explaining these trends.

No sexual partner

The researchers used data collected as part of the General Social Survey, a nationally representative survey of US adults that includes members of the current millennial generation and its predecessor, Generation X. In total, they looked at the answers of 26,707 adults regarding sex and relationships.

The researchers discovered that 15% of people who were born in the 1990s reported having no sexual partners since the age of 18 compared to only 6% of Generation X individuals, when they were in the same age group. Far from hooking up with multiple partners, a larger proportion of young adults than before are not having sex at all.

And contrary to the theory that online dating increases the odds of having sex, the authors of the study believe it might actually contribute to many Millennials not being sexually active.

"Online dating apps should, in theory, help Millennials find sexual partners more easily. However, technology may have the opposite effect if young people are spending so much time online that they interact less in person, and thus don't have sex," said lead author Jean M Twenge, from San Diego State University.

Safety first

Other factors behind this relative abstinence among Millennials may be the importance they give to safety. Widespread reports in the media about sexual abuse and sexually-transmitted disease may discourage sexual interactions.

"This is a very risk-averse generation, and that attitude may be influencing their sexual choices", Twenge added.

Furthermore, the socioeconomic context does not facilitate hooking up. The historically high number of young adults living with their parents and the later age at first marriage, for instance, could be to blame.

Although not having sex after the age of 18 still only involves a minority, the study suggests it could have important consequences in the future on the strength of romantic relationships and well-being among Millennials.

"It's good news for sexual and emotional health if teens are waiting until they are ready. But if young adults forgo sex completely, they may be missing out on some of the advantages of an adult romantic relationship," Twenge concluded.