BRITISH men and women are now the most promiscuous of any big western industrial nation, researchers have found.

In an international index measuring one-night stands, total numbers of partners and attitudes to casual sex, Britain comes out ahead of Australia, the US, France, the Netherlands, Italy and Germany.

The researchers behind the study say high scores such as Britain’s may be linked to the way society is increasingly willing to accept sexual promiscuity among women as well as men. They also believe that, among certain age groups and at certain times, men and women are equally liberal.

The researchers say that cultural developments have meant women are now as able to engage in no-strings sex as men. “Historically we have repressed women’s short-term mating and there are all sorts of double standards out there where men’s short-term mating was sort of acceptable but women’s wasn’t,” said David Schmitt, a professor of psychology at Bradley University, Illinois, who oversaw the research.

The study was conducted by asking more than 14,000 people in 48 countries to fill in anonymous questionnaires. Respondents were asked about numbers of partners and one-night stands, and their attitudes were assessed by asking them how many people they expected to sleep with over the next five years and how comfortable they were with the idea of casual sex.

The results were combined into an index of so-called “sociosexuality”, the term used by evolutionary psychologists as a measure of how sexually liberal people are in thought and behaviour. Most individuals scored between 4 and 65.

The country with the highest rating was Finland, with an average of 51. Taiwan came lowest, with 19.

Britain scored 40, placing it 11th overall, behind countries such as Latvia, Croatia and Slovenia - but it was highest among the major western industrial nations. The first tranche of research was published in 2005 but analyses have continued and Schmitt described the latest in this week’s edition of New Scientist.

Britain’s ranking was ascribed to factors such as the decline of religious scruples about extramarital sex, the growth of equal pay and equal rights for women and a highly sexualised popular culture.

Schmitt says the ratio of men to women is one of the factors that determine a country’s ranking.

The high scores in many Baltic and eastern European states might be linked, Schmitt said, to the fact that women outnumber men and so are under more pressure to conform to what men want in order to find a mate. In Asian countries, by contrast, men tend to outnumber women slightly, so it is men who have to conform.

Schmitt’s findings are reinforced by earlier research showing that the British are more likely than other nationalities to have “stolen” other people’s lovers. A third of British men are in relationships with women they have poached from other long-term relationships, he found.

Among British women, 28% have apparently poached their other halves rather than formed relationships with single men. Only 17% of men in America had poached their girlfriends. In France only 10% of both men and women were poachers. In Germany the figures were 17% of men and 14% of women.

Schmitt said that in more liberal countries such as Britain women may even be becoming more promiscuous than men. Such trends are typified by the television series Secret Diary of a Call Girl, in which Billie Piper played a middle-class prostitute who relished her numerous sexual encounters.

One of the most intriguing ideas emerging from Schmitt’s and others’ work is that when women are at their most fertile they become even more willing than men to consider one-night stands.

There are, however, still key differences in the behaviour of men and women, especially regarding the ages at which they are most sexually liberated. Schmitt found that men tended to have the most partners, and to think most about acquiring new ones, when in their twenties. Women’s promiscuity and lustful thoughts tended to peak in their thirties.

PROMISCUITY RANKINGS OF MAJOR COUNTRIES*

1 United Kingdom

2 Germany

3 Netherlands

4 Czech Republic

5 Australia

6 USA

7 France

8 Turkey

9 Mexico

10 Canada

11 Italy

12 Poland

13 Spain

14 Greece

15 Portugal

*OECD countries with populations over 10m Source: David Schmitt, Bradley University

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