I'm a 40-ish woman with kids and I've not had sex with my husband for eight years. I've been having dreams about girls. Could my sexuality have switched?

DR THOMAS STUTTAFORD

Generations of doctors have speculated about the emphasis that deserves to be placed on homoerotic dreams when determining a person's sexual inclination. I found when I was working in the genitourinary clinic that a far better indication of a woman's sexual inclinations was revealed by a discussion of her reaction to the sight or feel of a boyfriend's penis, than by questions about her dreams. Many theories have been advanced to explain the importance of dreams in determining sexual inclinations, but detached, clinical evidence to support them is in short supply.

The prevailing belief is that only a relatively small proportion of people are either totally homosexual or heterosexual; most are a mixture of both. It is, therefore, not surprising that dreams that feature both sexes at some time or another are much more common than would be supposed by the prevalence of homosexuality in the population.

The definition of female homosexuality is all important in understanding your letter. Female homosexuality was formerly described as lesbianism or sapphism. The standard way now of referring to homosexual people, whether male or female, is to describe them as gay. Technically a lesbian is a woman whose sexual needs can be met only by another woman, but few people of either sex score six out of six in the Kinsey scale of heterosexuality or one out of six for homosexuality. Some degree of bisexuality is more common in women than in men, but this is not usually physically expressed and even less commonly displayed by sexual contact.

People who are in the middle of the Kinsey scale often have enough homosexual feelings to be able to have and even enjoy a sexual relationship with someone of their own sex, if their preferred choice is not available. These people are referred to as facultative homosexuals.

Those who are almost entirely heterosexual, the fives and sixes of the Kinsey scale, would be totally safe on a desert island with the most beautiful or handsome person from the same sex. Equally those who are totally homosexual, the obligatory homosexuals, would be revolted by the thought of close contact with the genitalia of the opposite sex. Although obligatory homosexuals might strike up a good personal relationship with the castaways of the same sex, their relationship would remain chaste.

It could be that, like many women, you have some homosexual leanings and that the lack of sexual outlet at home has caused this small element of a facultative homosexuality to colour your dreams. Contrary to the popular image of lesbians, I found when working in the clinic that an unexpectedly large proportion of the patients who confided to me that they were predominantly homosexual looked like every other kindly, middle-aged housewife. One such patient told me that she had erotic dreams about other women only when she had a very masculine boyfriend. When her current boyfriend had a strong feminine side to his nature, she dreamt only about men. She determined to test the depth of her homosexuality by sleeping with women. Although she enjoyed flirting with both sexes, she found that physical sex with other women was repellent. Once undressed, she was turned off rather than attracted.

Dr Thomas Stuttaford, The Times doctor, spent many years working in a genitourinary clinic

SUZI GODSON

In The Interpretation of Dreams (1900), Sigmund Freud suggested that dreams were “spyholes” into the unconscious that allowed us to explore fears, desires and emotions that we were too scared to process in a conscious state. Whatever. The imagination is the one place a woman can do whatever the hell she likes without having to worry about the consequences, or indeed, the thought police.

Thinking isn't doing, and if all women were held accountable for their fantasies, men would be very nervous. I suspect that your same-sex dreams are simply an indication that your sex-starved psyche has found a slight, admittedly lesbian, chink in your sexual armour. Eight years is an awfully long time to go without sex, particularly for someone who is married.

Coital frequency tails off in any long-term relationship. It drops by 50 per cent in the first year alone and that stat gets a further hammering with the arrival of children but, even so, for a married couple to deny themselves sex through most of their thirties is very unusual.

I guess your sexual withdrawal from the marriage might be explained by your confusion about your sexual orientation, but what's his excuse? Who is he dreaming about? And if you've started having lesbian dreams only recently, what were you thinking about for the other 7 years? The average age at which boys and girls identify themselves as straight or gay is 13, but there are, and will probably always be, a percentage of the population who go through their entire lives in denial about their sexuality.

Although history has rewritten the 1960s and 1970s as the era of sexual liberation, in reality it was difficult for the average girl to develop a heterosexual identity 30 years ago, let alone a sexual identity that did not conform and would not be accepted. Unlike other minority groups, who could at least find solace with their families, lesbian and gay teens in the 1970s rarely had supportive parents and, unsurprisingly, as a result of this prejudice, some of them suppressed their natural instincts and went through the motions of heterosexuality.

This may or may not be the case with you, but the only way you will find out why you are not having sex - with anyone - is by investing some time in understanding yourself. When I read your question to Gail Simon of the Pink Practice (www.pinkpractice.co.uk), a private practice of registered lesbian and gay counsellors and psychotherapists, she replied: “It would be interesting to know how you feel about the idea of having a sexual relationship with a woman while you are awake?”

Whether your same-sex dreams are symptomatic of your sexless marriage, or a Freudian disguise for the “fulfilment of a repressed wish”, you and your husband have some serious talking to do.

Weirdly, it is often better to tackle the really awkward stuff with a third party to adjudicate. If face-to-face counselling feels too intimidating, you could start with Relate's telephone- based service (0300 1001234; www.relate.org.uk/wantadvice/counsellingbyphone). Sessions can be by yourself, or with you and your husband. You can't rewrite your history together but you can, and should, do something to ensure your future happiness. Good luck.

Suzi Godson is author of The Sex Book (Cassell, £16.99) and The Body Bible (Penguin, £16.99)

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