Q I’m 36, male and celibate for spiritual reasons (one lapse in eight years). I’ve been told I’ll get testicular shrinkage and become infertile if I go on. Is this true?

DR THOMAS STUTTAFORD

A Male sexuality is bedevilled by superstition and myth. The old adage that if you don’t use it, you lose it applies to some organs or muscle groups but not to a man’s testicles, even if he is entirely celibate.

You haven’t described what you mean by celibacy. Strictly speaking, celibacy means being committed to total sexual abstention, especially for religious reasons. Physiologically there is no difference between sexual intercourse and masturbation, although I suspect that to a fundamentalist both could, according to the circumstances, be considered sinful. Furthermore, even a saint has nocturnal emissions.

Your friends may be extrapolating from what happens to underused limbs or the eyes. If someone doesn’t use a limb after an accident, the muscles waste. Any loss of muscle power then needs to be rebuilt during recovery. Similarly a child learns to disregard the vision from the less dominant eye if born with double vision. The rejected eye becomes useless unless the muscular imbalance causing the double vision can be corrected surgically before primary school age.

The “use it or lose it” adage can apply to a man’s sexual prowess but only in relation to potency. It is not related to his fertility or testicular size. Even when potency is affected by a period of complete abstinence from sexual activity it is likely that a man’s ability to have erections had already been failing before the period of celibacy started. An inability to maintain an erection can force celibacy on a man, and this can sweep away his sexual confidence. And sexual confidence is essential if someone is to be potent.

Although celibacy doesn’t result in any shrivelling of the testis, lack of sexual activity of any sort may cause the penis to decrease in size, both length and breadth. Any part of the anatomy can be stretched, hence the pictures in old-fashioned school geography books of Africans whose earlobes have been enormously stretched by wearing ever greater weights.

Testes shrink and become softer to some extent as men grow older. Their fertility also falls. These tendencies are not related to underuse and neither should be apparent in any 36-year-old who has normal levels of testosterone. Testosterone levels fall with age and it is the resulting change in the oestrogen/testoster-one balance that is thought to account for smaller testes. Also, in older men, less of the circulating testosterone is available to the body’s tissues to influence male primary and secondary sexual characteristics. Probably the people who have been talking to you about testicular shrinkage may have been confused by research that showed that after a vasectomy (the snip) the testes of many animals including some primates shrink a little. However, it is doubtful if this could be related to any subsequent impotency.

If you are worried about your testicular size, consult a genitourinary specialist. Most clinics have a set of modelled testes beautifully carved in an earlier century from fine hard woods. These are used for comparison so that a patient’s testicular size can be classified as being normal or otherwise. The firmness of the testes needs to be judged by an experienced doctor.

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

SUZI GODSON

A Last week while I was pondering your dilemma I heard a Radio 4 programme about self-storage. A reporter went into one of the growing numbers of storage units that are scattered around the edge of most British cities and asked people what they kept in their units and why they bothered paying £100 a month to store an old sofa or their childhood chemistry set. All of the people interviewed said that they hoped to be able to use them again one day. When they had a big house to furnish, or a small child to entertain, they felt they would be glad that they had kept their “stuff” and the money spent preserving it would be cash well spent.

As I listened, it struck me that if you were genuinely committed to a lifetime of celibacy, you wouldn’t be too bothered about whether your fertility was going to be affected by your decision to abstain from sex. After all, why worry about maintaining the mechanics for conception if you have no intention of ever using them? Without wishing to question your present motivations, I would urge you to consider the possibility that it is perfectly feasible to integrate spirituality and sexuality. Should you feel conflicted by a desire to find a partner or have children, you might remind yourself that a US study of 3,180 people carried out between 1997 to 1998, suggested that people who associated their sexual experiences with their spirituality were more likely to report a better quality of life and better relationships.

Most world religions embrace deliberate abstinence from sexual activity in some form. In her book A History of Celibacy (Lutterworth Press, £15), Elizabeth Abbott points out that in the past celibacy was a useful tool for religious groups. Sex was considered a threat to virtue and obedience and, in all likelihood, if it hadn’t been required for reproduction it probably would have been abolished altogether. Even in the 21st century, pro-celibacy or sex-negative attitudes are still deeply embedded. Any sensitive alien landing on Earth would be justifiably confused by the way sex is portrayed in our media. Alarmist headlines and moral editorials on teenage sex, STI epidemics, porn, addiction, infidelity, swinging, dogging, rape, abuse or paedophilia continually remind readers that sex is a primitive instinct over which human beings have no control.

For the gentle spiritualist it must be easy to conclude that taking a vow of celibacy is the only way to steer clear of the cesspit of human sexuality. But although sex can be reduced to a biological imperative, it is important to remember that for most people sex is humanised by love, surely the most spiritual of all emotions. Despite the rabid press it gets, out here in the secular world sex is still intricately interwoven with intimacy, hope, commitment and the pitter-patter of tiny feet. Besides ensuring the survival of the species, a flurry of surveys has indicated that regular sex has psychological and physical benefits, too. It stops Welsh men having heart attacks, keeps Swedes living longer, and prevents Canadian men getting depressed. But I digress. Fertility declines naturally with age in both men and women, but will abstaining from sex make you infertile? Um. No.

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

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