ROSEMARY BEECH, now in her late thirties, has had excess hair on her face and body since she was a teenager. When she was young, her mother used to bleach it every night, using a toothbrush; after her marriage, she shaved every morning before her husband woke.

'By the time I was in my late twenties, my body hair had become horrific,' she says. 'I had what can only be described as pubic hair going all down my back and over my stomach.'

Eventually Mrs Beech insisted that her family doctor refer her to a dermatologist. It was discovered that she had a hormone imbalance and she was given drug therapy. 'After three months of treatment my excess body hair began to disappear,' she says. 'I'm still left with quite a strong black growth under my chin, but, believe me, that is a minor detail. Now I can swim and enjoy the summer. I've been on the treatment for 12 years and life is now worth living.'

Skin that is smooth, peachy and almost totally hairless is a perfect feminine ideal: for a woman, a five o'clock shadow can make sexual relationships impossible.

'They're frightened someone's going to say you've got a beard or moustache,' says Catherine Thornton, who runs Face, a support group for people with unwanted hair. 'If you're in bed with someone, the last thing you want to be told is that you look like a man.'

Endocrinologists estimate that 1.5 per cent of women in the West, including those from ethnic minorities, are hirsute, with hair growing on the face, trunk and limbs. The cause is abnormally high levels of male hormones.

Most specialists, however, refuse to accept a strict medical definition of hirsutism. Dermatologists will treat any woman who considers herself too hairy - and 10 per cent of women with 'normal' hair feel that they have excess hair.

Ms Thornton says that since setting up Face six weeks ago, she has received more than 4,000 letters from women, and some men, whose lives revolve around a ritual of removing excess - or what they perceive to be excess - facial and body hair. Yet 90 per cent of women who have written to her have hair growth that would be considered 'normal'.

Many women who consider themselves too hairy spend hours in the bathroom every day, furtively shaving and plucking. Some shave while their partners are out or sneak into the bathroom before anyone else wakes up. Others take their razors to work, refuse to let anyone touch their face, or go anywhere where their routine might be upset. Some live in horror of having to go into hospital, for fear that their family and friends might see them slowly becoming hairier. And it is not just adults; girls as young as 10 are shaving regularly.

Even men are becoming affected by the hairless ideal: not a single hair sprouts on the well-oiled chests of the the Chippendales, and beauty therapists say that the number of men demanding chest waxes and electrolysis has increased dramatically.

Ms Thornton experienced painful and scarring ingrowing facial hairs and spent five years and several thousand pounds on treatment to remove them. 'If you walk around the street, you would be hard-pressed to find that many women with hairy legs,' she says. 'So wherever these women look, they see women who are hairless. When they look at their own hair, they perceive it as excessive.

'When they go to the doctor and find there's no hormonal imbalance, they feel isolated, which makes the problem worse. There's nobody to say, 'Well, actually, I've got hair growing there, too.' '

Stephen Franks, professor of reproductive endocrinology at St Mary's Hospital, London, accepts that a woman's perception of her hair growth is reason enough for treating her - even if the growth is minimal.

'You can have some women whom we wouldn't consider hirsute, but who find it traumatic to have to remove one or two hairs from their lower abdomen and their legs regularly,' he says. 'Others have enormous amounts of facial hair and don't think anything of it.

'Unwanted hair can have a profound effect on a woman's personal and working life. It's not unusual to see women whose lives have been severely blighted because of it.'

Severe hirsutism in women can be caused by an increase in the sensitivity of the skin to normal levels of the male hormone testosterone. This results in some hair follicles producing more vigorous growth than others. But excess hair is more likely to be caused by polycystic ovary syndrome, a condition now thought to affect one in five women. Instead of one ovarian follicle ripening and producing an egg, several follicles compete against each other: this results in the overproduction of male hormone.

Although little can be done to treat the ovary itself, the excess hair that results can be treated with hormone therapy and electrolysis. There are few side- effects to hormone therapy, but if it is stopped, the hair returns.

Researchers, mostly in America, are now looking at the enzyme that converts testosterone into its more active form, dihydrotestosterone (DHT). This is the hormone responsible for masculine traits in both men and women. Men born without the enzyme fail to grow chest and facial hair.

The enzyme is produced in both the prostate gland and the skin. While there are drugs available that will block production in the prostate, the researchers are concentrating their efforts on finding a way of inhibiting production of the enzyme in the skin.

It can take considerable courage for a woman with unwanted hair to visit her GP. Julian Barth, a dermatologist at Leeds General Infirmary, says that most women would be content with a reassurance that they are not turning into men. 'That is their greatest fear, especially the ones who are becoming very hairy,' he says.

Often the problem of unwanted hair is dismissed by GPs as cosmetic, not worthy of medical attention. Women are told to shave - or worse. 'One doctor told a 33-year-old woman to go and join a circus,' Ms Thornton says.

Howard Jacobs, professor of reproductive endocrinology at the Middlesex Hospital, London, believes that some GPs trivialise the problem. 'GPs will often say things like, 'It runs in the family', to which I reply, so do polycystic ovaries. Or they might say, 'It's normal', meaning 'I think it's normal', paying no attention to the patient's assessment.'

Research carried out by Professor Jacobs indicates that polycystic ovary syndrome may be linked to disturbances in blood cholesterol levels and blood pressure. He says that a woman visiting a GP's surgery with excess hair should always be referred.

Some women are unaware that excess hair can be treated and removed completely, and part of Ms Thornton's work is to inform women of the treatments and to reassure them that they are not alone.

'A lot of women are unaware that there are alternative methods to shaving, such as electrolysis,' she says. 'Some are frightened to have electrolysis, because they have heard horror stories about scarring. Some women can't afford it.'

Specialists believe that the fear of rejection for being 'hairy' is often baseless: some men like hairiness in a woman, and most accept their women, hair or no hair. Nevertheless some women are teased about their excess hair. One woman relates how she was sitting on a train when a man commented on the hair growth on her face. 'He laughed about it with other passengers, then went a step further and touched my face and commented on it again. I felt like dying.'

In the past, women were condemned as witches if they had excess hair, Ms Thornton says. 'You would have thought that in our educated society all that would have gone - yet even young children make jokes about it.

'I would like to see society accept the fact that most women have more hair on their bodies than tresses at one end and a 'dinky little triangle' at the other.'

Face, PO Box 484, Cambridge, CB4 3TF.

British Association of Electrolysists, 18 Stokes End, Haddenham, Bucks HP17 8DX (0844 290 721).