Health: When masturbation can be fatal: The practice of auto-erotic asphyxia is often concealed by a coroner's verdict. Monique Roffey looks at a lethal taboo

ONE EVENING last July a young man in his late twenties was found dead in his sitting room. He had hanged himself. Oddly, his head and shoulders were suspended from a noose only about three feet from the floor and his legs and torso were in a reclining position. Pornographic magazines were found, open, next to the body.

At the inquest into the young man's death, the coroner, Dr Peter Dean, recorded an open verdict. He was not convinced it was a case of suicide. 'There was the immediate possibility that this was an auto-erotic death,' he says. 'I couldn't say definitely that the man intended to take his life. Hanging himself was a deliberate act, but it had taken an unforeseen turn.'

Auto-erotic asphyxia is a method of increasing sexual excitement by restricting the oxygen supply to the brain, usually by tightening a noose around the neck. Although usually associated with hardcore sexual masochists it often arouses interest among the less experienced - curious schoolboys and young men keen to experiment with masturbation in the belief that the practice heightens sensation at orgasm. While rumours about how and why to do it abound in all-male locker rooms and dormitories, what is not passed on is the fact that it can be fatal.

'When pressure is put on the vagus nerve in the neck, instantaneous death can happen,' explains Dr Dean, a coroner in Essex. 'The sudden increase in pressure sends a message to the heart to shut down and a sudden cardiac death will result. This is why this practice is immensely hazardous and extremely dangerous.'

The vagus nerve plays a major role in the human nervous system, travelling from the brain-stem to all the major organs. Pressure on it can slow down the heart-beat and even stop it completely.

The Kinsey Institute's New Report on Sex, published in 1990, describes auto-erotic asphyxia as 'the deliberate reduction of oxygen to the brain - temporary suffocation. The belief is that it enhances orgasm, but no research has ever verified this effect.' Even those victims who believe they have constructed reliable 'self-rescue' devices, such as slip knots in the noose or a chair beneath it, often die during this practice. They do not realise that once they restrict the amount of oxygen in the blood they may lose consciousness before they can release the pressure applied to their necks.

Dr John Bancroft, clinical consultant at the Royal Edinburgh Hospital, also points out that the danger of the practice is compounded by the fact that it is secret behaviour. 'If something goes wrong, there is no one to rescue you.'

The prevalence of auto-erotic fatalities is difficult to calculate, since a coroner often records a verdict of accident or misadventure. It is under these labels that many auto-erotic deaths lie hidden. Sometimes, however, where uncertainty exists over whether the person intended suicide, the verdict is left open. Bereaved families usually prefer this. 'They often find an open verdict a little easier to accept, certainly easier than misadventure which might imply unsuspected goings-on,' says Dr Dean.

Although statistics have never been recorded in Britain, one US study estimated that there are between 500 and 1,000 deaths from auto-erotic asphyxia every year. An analysis of 135 such cases by the FBI found the average age of the victims was 26.

The secrecy surrounding auto- erotic asphyxia only increases the ignorance about its hazards. While Alex Comfort in The New Joy of Sex (Mitchell Beazley, 1991) calls people who want to be strangled 'idiotic' and warns his readers 'never do anything so damned silly', in general, educational books and articles about sex are rarely explicit about the practice and its associated dangers. The risk of being an example for copycats is too great.

Strangling oneself or others for sexual pleasure is, however, depicted in the Marquis de Sade's Justine (published in 1791) and William S. Burroughs' Naked Lunch (published in 1959); it also features in In the Realm of the Senses, a Japanese film first shown in 1976. Auto-erotic Fatalities (published by Maxwell MacMillan International), by Dr Park Elliot Dietz, a leading American forensic psychiatrist, is the only book ever written on the subject.

After analysing 150 cases, Dr Dietz said his research indicated that 'nearly all persons repeatedly engaging in this behaviour suffered from a psychosexual disorder known as sexual masochism'. But, he added, it is also a practice anyone attracted to danger might try.

'There's something in some people which leads them into strange sexual practices,' says Dr Bancroft. 'It's a striving for intense pleasure, or maybe they don't get a satisfactory response from the more usual ways of getting sexual pleasure. Either way it's definitely a dangerous thing to try, and maybe this risk adds to the excitement.'

Strangling oneself for sexual pleasure is not an activity confined to men. A report published earlier this year in The American Journal of Forensic Medicine and Pathology detailed nine female cases of fatal or near fatal auto-erotic incidents in Adelaide, South Australia. Two of the deaths were initially, and wrongly, assessed by coroners as homicide, and one as a suicide. All but one of the women had rigged up a self-rescue device that had failed. Two bodies were found with extra sexual props or aids such as vibrators.

The report also cites the distinguishing features of auto-erotic death: the absence of a suicide note or history of depression; a self-rescue mechanism to reverse neck compression; padding around the neck to prevent detectable rope burns or bruises; and the performance of the act in private.

As long as auto-erotic asphyxia remains a taboo subject it will continue to claim victims, be they serious sexual fetishists or ignorant schoolboys. In a rare article published by Vanity Fair less than a decade ago, a parent whose teenage son died from auto-erotic asphyxia called it 'history's best kept secret'. That is still an accurate description.