Dr Thomas Stuttaford

The Creator hasn't followed the same pattern when making every human penis. Even in men of the same racial origin, the flaccid penis may differ in colour, length and breadth; differences that are usually accentuated during erections.

Increasing age is the usual cause of a change in the angle of the penis during erection. In young men, the fully erect penis points upwards, while in middle age, it is at a right angle to the abdominal wall. In old age, even if a man has retained the ability to have a firm erection, the head of the penis points to the floor.

The change is the result of a loss of elasticity in the fundiform and suspensory ligaments that support the penis and attach it to the lower abdominal wall and the pubic bone.

Elasticity in ageing human connective tissue behaves like the elasticity of an old elastic band. Once either becomes worn, elasticity is lost and the ligaments, or the band, is permanently stretched. As a result, an erect penis that once pointed to the stars now points straight ahead or towards the woman's feet.

There are two objections to the theory that your son's troubles are the result of a loss of elasticity. First, the change in the fibres usually doesn't make a difference until middle age - and your son is only 27. The other clue is your phrase “it won't become fully erect”. This suggests that he is suffering from some degree of erectile dysfunction rather than a problem of angulation (not that this usually makes any difference to penetration).

Until the past 20 or 30 years, it was widely taught that 90 per cent of erectile dysfunction had a psychological origin. It is now believed that the fundamental cause in about 75 to 80 per cent of cases is physical rather than psychological, although both factors co-exist and exacerbate each other.

Unfortunately, once a man has, in his opinion, made a fool of himself by failing to have a workable erection, his confidence is likely to become badly dented. Next time he attempts intercourse, memories of his earlier failure is likely to increase his anxiety and he does even less well. The boost that Viagra, Cialis or Levitra provides can be an enormous help, even in young men, and should be tried in these cases.

Before erectile dysfunction is determinedly attributed to some psychological cause, it is important to check vascular, neurological and metabolic systems.

Tactful questions should also be asked about alcohol intake and recreational drugs, even smoking, as these may contribute to impotency. Some medicinal drugs aid potency but others may compromise it. If your son is taking any medication, he should consult his doctor about its side-effects.

Even the state of the spine is important. I was once consulted by a man of about your son's age who had been impotent and a bed wetter since savage beatings at school. The psychologists told him that the beatings had caused lasting emotional damage. Possibly, but X-rays revealed a congenital defect of the bones of his lower spine. They provided inadequate protection for his spinal cord, which meant that it had been irretrievably damaged by his housemaster's cane.

Dr Thomas Stuttaford, The Times doctor, spent many years working in a genito-urinary clinic

Suzi Godson

My initial reaction to your question was one of surprise. Call me old-fashioned, but I would have thought that any normal 27-year-old male would rather flambé his own intestines than share his sexual difficulties with his father. Lordy, I could barely bring myself to tell my parents that I was pregnant because it meant admitting that I had had sex - and I had been married for four years.

There does seem to be a natural boundary to what you should share with your parents once you are over the age of consent, but on the off-chance that I am just oversensitive, I read your question to a few male friends and asked whether they would discuss their private parts with their parents.

The answers ranged from: “He's 27, for God's sake. Shouldn't he be able to make a doctor's appointment by himself? to “over my dead body, I'd never discuss my todger with my dad”. One friend said that he might talk to his old man “but only in blokeish terms and nothing too specific”, such as “I had the strangest pain in my old chap last week” as opposed to “it's one inch thick at the hilt, narrowing to half an inch at the end”.

You clearly have an exceptionally close relationship with your son, but in this situation you are not equipped to help him. An inability to achieve a firm erection in someone so young can indicate underlying health problems, so it is important that he sees a doctor as soon as possible. He could begin with a GP appointment and ask for a referral, but probably he would be better off making an appointment at the Jane Wadsworth Clinic, an internationally acknowledged centre of excellence for the treatment of sexual health problems. Part of the Jefferiss Wing at St Mary's Hospital in Paddington, West London, it is run by Dr David Goldmeier, an expert in sexual dysfuntion. Alternatively, he could go to a private clinic. The Dr Thom clinic in East London specialises in sexual health; a consultation for erectile dysfunction is £100, excluding tests.

It is vital to find a cause and a cure for his erectile difficulties because, as you rightly point out, it is bound to have affected his confidence with girls. If you want to understand more about the negative cycle of performance anxiety, there is an intelligent, often amusing, explanation of it at www.head-cleaners.com/perfsex.html , in which hypnotherapy is suggested as an effective treatment. Although hypnotherapy isn't normally associated with the treatment of sexual dysfunction, Patrick Browning, a clinical hypnotherapist who practises in Kensington, West London, has recently begun using trance to help patients suffering from sexual disorders. Even if your son's problems are physical, hypnotherapy would be a useful tool for building up his self-esteem and his confidence. As Browning explains: “Hypnotherapy helps to make changes in the unconscious mind which is where our habits and our learnt responses reside. The conscious mind may want to change an aspect of our behaviour, but it is extremely difficult to do so unless the change is also made in the unconscious.”

The downside for you, of course, is that once your son has a fully functioning set of tackle and a girlfriend, you won't see him for dust.

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

OVER TO YOU

Do you have a sexual dilemma for Suzi Godson and Dr Thomas Stuttaford? Send your e-mails to body&soul@thetimes.co.uk or write to Body&Soul, The Times, 1 Pennington Street, London E98 1TT. The authors regret that, although your letters are much appreciated, they cannot respond personally.

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