Sexual lifestyles in Britain have "changed substantially" in the past 60 years, surveys suggest.
More than 15,000 men and women aged 16 to 74 participated in interviews between 2010 and 2012. The findings were compared to two previous surveys from 1990 and 2000 and appear in Tuesday's issue of the journal The Lancet.
Half of respondents reported having sex at least three times in the last month compared with five times during the first survey.
Kaye Wellings, head of social and environmental health research at the London School of Hygiene and Tropical Medicine, was one of the leaders of the research. The decline in frequency occurred as the financial crisis hit and as technology increased, she said.
"People are taking their iPhones and iPads into bed," Wellings noted. "They're also working harder and maybe have less time for sex," she said.
The findings included:
- Half of Britons had sex by the age of 17, about the same as 20 years ago.
- The proportion of women who had a same-sex experience since the first survey was done in 1990, increased from 4 per cent to 16 per cent. In comparison, the number of men who reported a same-sex experience has remained at about 7 per cent since 1990.
- On average, the number of sexual partners reported by women doubled, from four to eight, whereas the number for men rose from nine to 12.
Public health programs need to embrace the evidence of change to promote "informed, consensual, safe, respectful and pleasurable relationships," the researchers suggested.