SUZI GODSON

You don't say whether you are single or whether you masturbate regularly, but the late onset of your nocturnal emissions suggests that something in your personal circumstances has changed. Are you taking medication or suffering from an androgen deficiency? In a study published in The Journal of Clinical Endocrinology & Metabolism, boys given extra doses of testosterone reported an increase in nocturnal emissions from 17 per cent to 90 per cent.

Do you drink a lot at night and forget to pee before you go to sleep? Do you sleep on your back? Wear tight pyjamas? Sleep in a bed that is too warm? Or are you consciously abstaining from masturbation for religious reasons? Back in 396 Saint Augustine of Hippo, a father of the Latin church, struggled with the sexual stain of nocturnal emissions, but today, even the Catholic Church acknowledges that it would be unfair to consider an involuntary reflex a sin.

The general consensus on “wet dreams” is that they are a “safety-valve” for excess semen not released through masturbation or intercourse. Alfred Kinsey, the greatest chronicler of American sexual experience, disagreed, however. The son of a strict Methodist, Kinsey was taken to church three times every Sunday as a child and he figured that if wet dreams were an overflow mechanism for unused semen, devout church-going men who had no other outlet for their sexual urges would experience nocturnal emissions more frequently.

Although there seems to be a correlation between higher frequencies of nocturnal emissions and lower rates of masturbation, Kinsey found no difference between the emission rates of the churchgoing and the non-churchgoing. Rather than presuming that an increase in sexual activity would decrease involuntary emissions, Kinsey suggested that frequent nocturnal emissions might just as easily be a psychological mechanism by which sexual tension is relieved in a way that absolves a man of the desire, or the need, to masturbate.

Kinsey's theory seems to be supported by An American Seafarer in the Age of Sail: The Erotic Diaries of Philip C. Van Buskirk. Van Buskirk's detailed records of his masturbation, nocturnal emission and coital activity between 1852 and 1858 are illuminating. Initially, his diaries show his nocturnal emissions matching his levels of masturbation almost identically. When he gives up masturbation in 1855 his nocturnal emissions increase dramatically, peaking at 69 emissions in 1858 when the records thankfully cease.

Kinsey's records estimate that 83 per cent of men in the US experience wet dreams at some point. The frequency varies depending on age and marital status. For single 15-year-old males the average is 0.36 times a week while for 50-year-old married men it is 0.15 times a week. Which adds up to extra laundry, but not much else.

There is some good news, though. A Harvard study has found a positive link between increased ejaculations and good prostate health.

DR THOMAS STUTTAFORD

What is striking is that your wet dreams became frequent enough for you to suggest that you were “suffering” from them only when you were 40.

Most males find that wet dreams are most prevalent during adolescence. Nocturnal emissions become less frequent as men become older and testosterone levels fall. By 40 few have to worry about nocturnal emissions.

The amount of subconscious activity involving the genitalia of a sleeping male is surprising. It is thought that were it not for the inhibitions imposed by a conscious mind, men would have as many erections while awake as asleep. Research workers in 1965 used penile monitors to determine how much of the night a sleeping man's penis was erect or near erect. They showed that all healthy males aged between 3 and 80 had some penile engorgement during the night. The penises of healthy adult men are to a greater or lesser extent tumescent for 40 per cent of the night. In 80 per cent of the occasions when there is a full erection the man has rapid eye movement (dream-laden) sleep. Another piece of research demonstrated that the normal man in a good state of health has three to five full erections nightly.

Although nocturnal erections occur from infancy onwards, nocturnal emissions, wet dreams, start only after puberty has become established and the male is producing semen. A man's fertility is dependent on the number and quality of the sperm. A man who ejaculates infrequently may have a higher sperm count, but the quality of the sperm may be reduced and their ability to swim fast in a straight line compromised.

Conversely, a man who ejaculates more often than usual may have a lower sperm count, but the sperm may be more active and vital. Most doctors believe that the ideal should be a compromise between the two extremes.

This has given rise to the theory that wet dreams are nature's method of insuring that even if a man has an uneventful sex life the balance of old and young sperms will be maintained and that he is ready to impregnate should the opportunity arise.

Anxiety dreams, dreams that are frightening, violent or are rendering the dreamer frustratingly incompetent and vulnerable are associated with a reduction in nocturnal erections. These may also be reduced by any drugs or disease that produces impotence or a loss of libido. Low mood or depressive symptoms do the same.

Anecdotal evidence has it that men who, although cheerful, have few physical sexual outlets, no girlfriends, other partners or even a talent for fantasy are more likely to have wet dreams. There are other unproven but widely-held beliefs such as that pressure on the genitalia increases the likelihood of wet dreams. This pressure could be from tight clothing or a full bladder. The number of nocturnal erections and emissions may be reduced by medication, drugs or drink. Have you changed medication, altered your drinking habits, are you happier, healthier, or do you have less opportunity for overt sexual activity than previously? Any of these could account for the change in you.

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

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

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