For more than 20 years I have worked as a psychotherapist. In other words, I am one of the many tens of thousands of mental health colleagues in Great Britain who devotes his or her daytime life to the treatment of people who struggle with, or suffer from, a wide range of psychological problems. I completed a lengthy training and apprenticeship which included many years of university-based study in clinical theory and research methods, many years of working in psychiatric hospitals and community mental health settings, many years of supervised psychotherapeutic work, as well as undergoing intensive psychoanalysis myself, all of which has helped to prepare me for my profession.

For most of my career I have worked principally with individuals, but some time ago I decided to undertake five further years of specialist postgraduate training in “marital psychotherapy”. Working with couples has made me even more concerned with sexual matters than before. An individual patient might spend a whole 50-minute session telling me how much she hates her evil, persecutory boss; or he might launch into a monologue about the horrors of his teenage children. But with couples, people who come because they can no longer live together under the same roof, or share the same bed, one cannot avoid the question of sexuality.

I would be hard pressed to recall any couple who presented for marital psychotherapy with a healthy sex life. As we may not fully appreciate, sex might be the most sensitive barometer of the solidity of the relationship between husband and wife, or between two lovers; and when the gremlins of infidelity or inattentiveness or other forms of cruelty enter the relationship, then the sexual life will suffer as a consequence.

Let us begin our examination of the British bedroom with an investigation of the sexual orientation preferences of the nation.The statistical analyses of data for the British Sexual Fantasy Research Project are drawn from the results of a questionnaire administered by YouGov, the polling organisation.

Out of more than 34,000 people to whom the questionnaire was sent, there were 13,553 principal respondents. The lengthier vignettes and case histories of sexual fantasies featured in the book derive principally from the confidential clinical psychodiagnostic interviews. In view of the fact that many research projects on sexual fantasy have relied upon samples of only a few hundred individuals, the British Sexual Fantasy Research Project can claim to be more highly statistically representative of the British population at large; and, to the best of my knowledge, at the time of writing, this study constitutes the largest published survey on the psychology of adult male and adult female sexual fantasies.

Just over 90 per cent of the country defines itself as heterosexual, and 3 per cent defines itself as homosexual, less than a third of the figure usually reported for homosexuality. Of course, if one includes the self-defined “bisexual” individuals, as well as that small but still marked percentage of people who would regard themselves as “undecided”, then we have a somewhat higher percentage for whom homosexuality may be a serious option: 8 per cent rather than 3 per cent. Irrespective of whether they have sex with heterosexual, homosexual, bisexual, bi-curious or undecided partners, many people will be quite keen to know the answer to some critical questions: “How often do other people do it? And am I getting enough by comparison? Just what is the national average?”

Contrary to what one might imagine, a very large percentage of British adults admitted having no sex at all at the present time. As many as 18 per cent of contemporary Britons do not currently engage in sexual behaviour with a partner, which translates to approximately 8.1 million people. This figure combines the 2 per cent of celibate Britons who have never had sexual relations with a partner with the 16 per cent who have had sexual experience or experiences in the past but now live without regular sex. This cluster of 18 per cent of behaviourally sexless Britons may well have fantasies and desires, may well masturbate or use pornography; butthese individuals do not engage in genital sex with another human being. In fact, British women have much less sex than British men: some 21 per cent of women, as compared with 15 per cent of men, have no sex, an amalgamation of those who have never had sex and those who have had sexual relations in the past but do not do so at present.

For the rest of the population who do have sex, frequency of sexual contact ranges from less than once each year to two or more times a day, seven days of the week.

As many as 32 per cent of British adults could be classified as low sexual frequency (less than once a month) practitioners, 44 per cent as medium sexual frequency(between once monthly and twice weekly) practitioners and only 19 per cent as high sexual frequency (three times a week or more) practitioners.

Most Britons have sex once or twice weekly, and most would be characterised as moderate indulgers in sexual activity with another person. In terms of gender differences, the data indicates that men and women enjoy approximately the same amount of sexual experience, with one striking exception.

Among those who have had sexual relations in the past but do not have sexual contact with others at present, women outnumber men considerably (19 per cent of women compared to 12 per cent of men). I have come to refer to this group of individuals who no longer practise sex as “neo-virgins”, a group which requires much more study by psychological researchers. In fact, as the number of single men and women in Great Britain increases, amid predictions that such a trend will continue, many people have begun to choose a single lifestyle as a more consciously motivated option. Again, this field of study has remained relatively neglected, and it would behove future researchers to devote more attention to the phenomenon of neo-virginity.

In terms of heterosexual behaviour, the British Sexual Fantasy Research Project data reveals that the average British heterosexual male will have had actual sexual contact, defined as “oral sex”, “vaginal sex”, “anal sex” or any combination thereof, with an average of 15.64 women during his lifetime. The typical British heterosexual female will have will have had comparable sexual contact with an average of 14.56 men during her lifetime. For both males and females, the average number of sexual partners rises across the life cycle, refuting the notion that most people pack their promiscuity into their teens and twenties. This seems not to be the case at all.

In terms of homosexual contact, the average British female will have had intimate sexual contact with 1.61 other women, and the average British male will have had intimate sexual contact with 7.46 other men. The substantially higher mean percentage of numbers of homosexual partners for men reflects the fact that a certain sub-section of British men will have had sexual contact with literally hundreds of other men, and this information skews the national average markedly.

In fact, approximately 1.8 million British adults will have had sexual contact with more than 100 partners during their lifetime. Although nearly two million adults will have had intimate genital contact with over 100 other people, the vast majority of Britons have only one sexual partner in any given calendar year, with men averaging 1.18 partners per year, and women somewhat more loyal at an average of 0.7 partners per year.

All percentages in this article have been rounded up or down Extracted from Sex and the Psyche by Brett Kahr, published by Allen Lane on February 22 at £25. © Brett Kahr 2007 www.penguin.co.uk. Available for £22.50 (including p&p) from Times BooksFirst: call 0870 1608080; timesonline.co.uk/ booksfirstbuy

A North-South divide?

In terms of geographical diversity, it seems that across the country, most Britons have roughly comparable amounts of sex, with the highest percentage of neo-virgins living in the South of England (excluding London), and the greatest percentage of high-frequency sexual practitioners living in Scotland and the North of England (though only marginally more than in other parts of the nation).

The first time

The average Briton will have had his or her first full sexual encounter at the age of 17 years, two months and two weeks. We can observe an historical cultural shift in British life, in that the average Briton of more than 50 will have lost his or her virginity at the age of 17.66; whereas the average Briton under 30 will have done so one full year earlier at 16.62. Clearly, the change in the age of consent, and the increasing acceptance of teenage sexuality for those aged 16 and above, has now begun to be reflected in the data itself. Social class also seems to play a role in the age at which Britons will have first experienced oral sex, vaginal sex, anal sex or any combination thereof. Those in social classes A, B and C-1 will have done so, on average, at the age of 17.66, whereas those in social classes C-2, D and E did so, on average, at the age of 16.67, almost exactly one full year before. Geography also influences the age of first intimate sexual contact, though to a smaller extent, with northerners more likely to lose their virginity first, at the average age of 16.97, as compared to Londoners, who do so last, on average six months later, at the age of 17.47.

Does age matter?

There is unquestionably a tailing off of high-frequency sexual activity after the age of 50. Those over 50 do have regular sexual experience, but not as many times each week as they would have done during their twenties, thirties and forties. When examining the highest frequency practitioners of sex, 1 per cent of 18 to 29-year-olds have sex more than once a day, as do 1 per cent of 30 to 50-year-olds. But the proportion of overfifties who have sex more than once daily registers at 0 per cent. The underfifties and the overfifties enjoy roughly comparable amounts of sex at a frequency of once or twice weekly, but far fewer overfifties manage three times a week or more. And when one considers four and five-times-weekly sex, the data reveals that the underthirties will be almost four times as likely to experience this frequency as the overfifties. So, although the data offers evidence of huge individual variation (with some teenage virgins and antiquarian practitioners of coitus), for the average Briton, the amount of sexual intercourse does indeed recede as we progress through the life cycle.

Infidelity

At least 42 per cent of men and 31 per cent of women have kissed another person while in an ongoing, regular partnership, yielding a national average of 36 per cent. Baldly speaking, nearly half of all married men, and nearly one third of all married women, have kissed someone else. In view of the fact that approximately 68 per cent of all Britons will be living in a steady marital or partnered arrangement, this means that according to the most conservative estimate, roughly 11 million Britons will have indulged in an extramarital kiss at some point. In terms of age differences, it does seem as though Britons become more unfaithful as time progresses. Of those aged between 18 and 29, 12 per cent will have had oral sex outside a steady relationship. For those aged between 30 and 50, the figure rises to 20 per cent, and for those aged 51 and older, 19 per cent will have engaged in extra-partnership oral sex. This information may be explained, in part, by the fact that many underthirties will not yet have forged permanent partnerships, hence their rates of extramarital sexuality will be lower automatically; and those underthirties who have already committed themselves to a partner may still find themselves in the first flush of romance, and might, thereby, practise fidelity more fully. But for the overthirties, the temptation becomes much more overwhelming. As for vaginal sex outside of marriage or an ongoing partnership, 14 per cent of the underthirties have participated in such activity, as compared to 23 per cent of the 30 and 40-year-olds. Most strikingly, among the overfifties, 30 per cent have had vaginal sex with someone other than his or her regular partner, a figure higher than the national average, across all age groups, for extramarital vaginal penetration. Thus, in spite of the decline in sexual practices across the life cycle, older people will still be much more likely to have engaged in extramarital vaginal penetration. As for social class differences, the upper income band and the lower income band practise infidelity in virtually equal numbers. As for geographical differences, someone’s postal address seems to make little difference to their likelihood of “cheating” Northerners, however, are slightly more likely to kiss, fondle and practise both oral and vaginal sex outside marriage, and Londoners are more likely to engage in anal sex outside marriage.

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