Young adults are engaging in less casual sex – and scientists may have uncovered why.
A study by Rutgers University in New Jersey reveals nearly two in five (38%) men aged 18 to 23 had commitment-free intercourse in a given month in 2007, falling to just under a quarter (24%) 10 years later. The proportion of women partaking in casual sex similarly declined, from 31% to 22%.
Perhaps reassuringly, a drop in drinking was found to be the biggest driver of young adults forgoing casual sex.
A rise in gaming and prolonged living with parents may also be responsible, however.
Research has repeatedly flagged young adults are having less sex, with one study suggesting 15% of 20 to 24-year-olds abstained completely in any given year from 2010 to 2014, a rise from 11% between 2000 and 2009.
In positive news, this may reduce unplanned pregnancies, sexually transmitted infections and even mental health problems, the Rutgers scientists wrote in the journal Socius.
On the other hand, "sexual inactivity may hinder young adults' psychosocial development, and diminish their physical and emotional gratification".
With there being little research to explain why casual sex is declining among young adults, the scientists analysed data from the Panel Study of Income Dynamics Transition to Adulthood Supplement.
This survey asked around 2,000 young adults how their sexual encounters changed over time.
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Results suggest a decline in drinking was the biggest driver of reduced casual sex – "encounters that occur outside of a committed relationship or partnership" – among the male participants; responsible for a third (33%) of the drop alone.
The men who drank every day were around 5.5 times more likely to have casual sex than those who never consumed alcohol, the scientists found.
A rise in gaming is said to explain a quarter (25%) of the men's changed sexual behaviour.
Those who played video games every day had less than half the odds of having casual sex than those without the hobby, the results suggest.
"The new generation of young adults became more individualistic and less social in real life, but more involved in social media and online gaming networks," said study author Lei Lei, a professor of sociology.
"The changes in how young people socialise affect their opportunity to have casual sex, which often serves as a trial or rehearsal for long-term romantic relationships."
The results also suggest living with parents was behind around 10% of the men's reduced casual sexual activity.
"The recent cohorts of young people adopt adult roles later in their lives and depend on their parents for longer periods," said Professor Lei.
"The declining engagement in casual sex among this age group could be another sign of delayed transition into adulthood."
Among the young women, only a decline in drinking was linked to reduced casual sex, with a lower alcohol consumption being attributed to a 25% drop in the activity.
The scientists stressed further research is required.
"Perhaps the intensifying concern with interpersonal sexual violence and sexual coercion as exemplified in the #MeToo movement has begun inhibiting presumably voluntary casual sexual encounters between young women and men," they wrote.
"The impact of this and other broad cultural shifts will also likely be difficult to measure, but may well require consideration in order to develop a comprehensive assessment of the decline in young adults' casual sexual activity."
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