Dr Thomas Stuttaford

Have you been watching too many recorded episodes of Little Britain? A variation on one of its regular sketches is of a young man introducing his girlfriend to his parents.

After introductions they all sit down for a formal meal. The young man looks fondly and pleadingly at his mother until she takes out her breast and squirts milk at him. He drinks it, to the horror of his would-be fiancée.

Most people would share the girlfriend's opinion. Even so, pictures of milk pouring from shapely breasts into the mouths of babies is a constant theme in classical art, while some men take pictures of their wives breast-feeding so that they may be reminded of the experience later.

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However, in most cases, breast-feeding appeals to onlookers because it arouses protective instincts, epitomised by the caring message of the Madonna and child image, rather than erotic longings.

One of my patients took her baby to a preview at an art gallery. When he began to cry she decided to unbutton her dress. lift up her bra and feed him immediately. She told me later that she was amazed by the small crowd of fascinated men, presumably art lovers, who gathered to look wistfully at her.

Many patients have told me that their wives' or partners' breasts became more alluring and sexually stimulating when enlarged because of pregnancy or lactation.

Western men usually react more to big breasts. However, Dr Desmond Morris, the expert on human behaviour, has documented how some cultures prefer small breasts - and how, in some parts of the world, neighbouring tribes may have different preferences. The emphasis that men place on the appeal of one part of the body can vary, even within the same culture. They might, for example, be “breasts” or “bottoms” men, but if their preference is strongly held, it is described as partialism.

Breasts have two functions. They are not only useful for feeding a baby - although only a small proportion of the breast is composed of glandular tissue, the rest is mainly fat - but also serve as sexual signals to attract mates.

The latter is something that happens only in human beings. In primates, as well as some other mammals, rounded bottoms are the principal sexual signal; breasts are important only for breast-feeding. Once we evolved and no longer walked on all fours, bottoms became relatively less conspicuous and breasts became the more important sexual signal.

Are you unusual? Probably the manifestation of your fascination for breasts and your desire to share your child's supper is a bit beyond what most men experience, and some people would find your erotic response to the idea of lapping up your wife's breast milk dis-tinctly weird.

But it is harmless, unless your wife objects. Even so, I should keep quiet about your fantasies.

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

Suzi Godson

The physical transformation that a woman experiences during pregnancy is fascinating and the ability to produce a substance nutritious enough to sustain a baby for the first year of its life is nothing short of miraculous.

Breast-feeding is deeply sexy and deliciously sensuous. Soft skin against soft skin. Shark eyes rolling with pleasure, and warm, wet, milky lips greedily sucking sweet vanilla cream. And when the baby wakes up, he gets his turn, too.

Sexualising your baby's sustenance might feel like a transgression, but it's not. Just because they are multi-tasking doesn't mean that your wife's breasts are off-limits; and since she will leak during sex, and spurt during orgasm, you can just clean up.

If, however, is the operative word. It's a well-known fact that the hormones associated with breast-feeding have a deleterious effect on libido.

Prolactin might stimulate breast-feeding, but it represses the effect of dopamine, the happiness hormone that is directly responsible for sexual arousal. Oxytocin, the hormone that encourages contractions, lets down milk supply and bonds the mother to the child, puts the last nail in the coffin of your wife's libido.

Oxytocin doesn't affect just human beings. In the animal kingdom it is the reason prairie voles form long-lasting pair bonds while montane voles don't. If you block oxytocin production in female rats and mice, they stop nurturing their young and lose the ability to recognise familiar members of their species.

So, how do you persuade a sleep-deprived woman, who hasn't had her highlights done and who weighs 15lb more than she used to, that breast-feeding her husband is anything other than exhausting?

Flattery is the best, possibly the only, weapon. Childbirth knocks the stuffing out of female self-esteem, so your sexual interest in her lactating breasts may be a welcome boost to her fragile ego. You could try explaining to her that the same hormones that are suppressing her sexual appetite are whetting yours.

Curiously, the odours given off by breast-feeding have been shown to heighten sexual desire in childless women. Researchers at the Monell Chemical Senses Centre in Philadelphia and the University of Chicago are not sure why, but in 2002 suggested that it may be a way that women signal to each other that the environment is a good one in which to reproduce.

Breast-feeding may be a complex evolutionary interaction, but it is a damn clever system. The more your wife's breasts are stimulated, the more milk they will produce. The flavour will change depending on what your wife eats and how much liquid she drinks, but, in general, breast milk tastes like slightly sweet vanilla milk.

Some men love it, others are grossed out by it, but most have tried it. Some of them unintentionally. Many years ago when some young male guests turned up to visit my new baby, I discovered that I had run out of regular milk. All that was in the fridge was a lone bottle of freshly-expressed mother's pride, so I poured it into a little white jug on the tray next to the bickies. No one noticed the difference.

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

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