Suzi Godson

If it is any consolation, you are not the only woman who allows vanity to limit her sexual repertoire. Once, while I was crawling around trying to pick random bits of lego out of the shagpile carpet, I found myself kneeling over a shatterproof mirror, which I bought for my twins when they were babies. Lordy, what a shocker. Gravity had pulled all the skin on my face away from my bone structure but my eyes remained recessed in my skull like little piggy jewels.

As I watched the flesh that was once my face flap around like some hideous Nasa experiment, I vowed never to go on top in bed unless my husband was wearing a blindfold.

Another girl I know installed one of those wall-to- wall mirrored wardrobes from Ikea in her bedroom and, as a result, became acutely self-conscious about the way she looked when having sex. She now confines herself to the missionary position because it inverts her stomach and makes her look about 10lb lighter. You might want to suggest this as an alternative because it also makes you look prettier.

Help, my sneezing spoils sex

I am a middle-aged man. Whenever I climax, I have a fit of sneezing which does rather spoil the mood

Background

• I'm turned on by my wife breastfeeding

• I eye up women when my wife isn't around

• Should my boyfriend be screened for sexual health?

• Is my friend a nymphomaniac?

• Will tantric sex help my love life?

Where gravity drags a woman down when she is on top, it gives her a beauty boost when she is lying back and thinking of pentapeptides. Take a look at Keira Knightley and Sienna Miller in the poster for their new film The Edge of Love. See how great they look? That's because they are lying down. God's honest truth.

Doggy in front of the mirror is probably the ultimate challenge to any woman's self-esteem. Most women are too self-conscious about their bodies to enjoy the sight of their partner thrusting into their XL rear end while their spare tyre and nipples graze the duvet.

We wish it weren't so, but the majority of women feel so insecure about their bodies that it interferes with their ability to enjoy sex. Two years ago, a Grazia magazine survey established that 98 per cent of British women hate their bodies and that the average woman worries about her body once every 15 minutes. Indeed last year a survey of 3,500 women by the bathroom company Shuc revealed that a third of women think they are too fat to appear naked in front of their partners.

In 2004 the magazine Psychology Today carried out a survey on body image and of the 3,452 women who responded, 15 per cent said they would sacrifice more than five years of their lives to be the weight they want; 24 per cent said that they would give up more than three years. Which is 100 per cent crazy, right? If men don't notice that you have had your hair done or are wearing a nice new dress, why would they notice that your spare tyre wobbles when you go on top. The male brain tends to perform tasks predominantly with the left side, the logical/rational side of the brain. Women, on the other hand, use both sides of their brains which means that they can transfer data between the right and left hemispheres faster than men.

In sexual terms it means that an aroused man thinks of sex alone, while his multitasking partner over-analyses their relationship, has a crisis of confidence about her body, orchestrates intimacy to limit the number of positions that will make her look like a wobbling tub of lard, has an orgasm and then reminds herself to get the lego out of the shagpile carpet.

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

Dr Thomas Stuttaford

Taboos are customs that are considered by mutual consent in any community to be wrong and, therefore, forbidden. They are not universal.

Venetians in previous centuries used to wear animal masks at carnival, a time when normal mores were overturned and temporarily abandoned.

In the United States there are groups of people known as furries, who dress up in animal skins and romp around; and the romping often includes sex.

It's a mistake to assume, even unconsciously, that sex from behind is bestial, brutish and is based on Fido's behaviour when randy. Nor is it only reversion to an earlier and more brutish and primitive stage in our evolution, when we walked on all fours.

Rear-entry positions can be more suitable for people with physical variations ranging from obesity in either partner to unusually small penises. It also offers easier and greater penetration, a possible advantage to either the woman or man.

In ageing men, whose potency is declining, and in women whose vaginas have become lax with time, rear entry offers a better grasp on the penis.

You don't specifically tell us whether it is sex in the doggy position that you dislike or whether it is sex in front of mirrors.

The objection to the latter arises because in some cultures sex is permitted only if procreation and not pleasure is its objective. Complete exposure of the female body is often not allowed, sometimes not even to a husband. So strict is this rule in some communities that sex takes place only with a sheet, fortunately with hole, between the lovers.

The use of mirrors, common in many continental countries, is not always encountered in Britain but even so wouldn't usually be considered perverse.

The objection to mirrors arises because it gives too great a prominence to the importance of bodily, including genital, appearance, and thus serves to discount other qualities. It is accepted that men have a more physical and visual approach to sex than women, who tend to emphasise its romantic, tactile and vocal aspects.

You don't write how long you have known your boyfriend. However, I assume that if this problem has arisen, you have known him long and well enough to be on terms sufficiently chummy to tell him exactly what turns you on, and off, sexually. Tell him, but be careful to avoid any suggestion of criticising him, for in most people's repertoires the doggy position is an acceptable alternative to face-to-face positions.

As it is variety that makes life interesting, you may occasionally want to conceal your feelings.

Remember that if you find either doggy position or mirrors irretrievably repellent you have every right to say so, as all sex, to be good sex, has to be consensual.

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

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