To me, giving birth is as personal as having sex," says Sarah, 24, from Essex. "You don't want someone else sitting there watching you." Sarah chose to "freebirth" her first child, now two, at home. Freebirthing involves giving birth alone, without a midwife and often even a partner or friend in attendance - Sarah delivered while her husband was in the next room. "I didn't have any experience of pain," she says, "there was just this really strong sensation that muscles were working. Then the baby's head appeared."

To prepare for the three-hour labour, Sarah had read everything she could on the subject, and says she "would have known instinctively if anything was wrong. As his head started to come out, I thought, I know the cord is around his neck." She flipped the cord over his head and, "He just flew out." As he was born, she says, she was laughing with joy.

Although rare in the UK, there is a growing online community of freebirthers or "UC-ers" (unassisted childbirthers) in the US who are celebrating "the primacy of autonomous birth". Laura Shanley, 49, from Boulder, Colorado, author of Unassisted Childbirth (Greenwood Press, £14.95) and veteran of five unassisted births, believes that "women are the true experts of birth. Birth is sexual and spiritual, magical and miraculous", she says, "but not when it's managed, controlled and manipulated by the medical establishment." Her website motto? "If you want the job done right, do it yourself."

"People think it's pretty crazy," admits Laura Field, 31, from Atlanta, Georgia, whose second child, Grace, nine months, was born at home, unassisted, after four hours. "Some people think you must be superwoman. Others think it's reckless. You get every reaction from awe to horror. I just feel like it was the most normal thing. It felt somehow life-changing and extremely ordinary at the same time." She is a member of a local group of 15 women who have had unassisted births. "There are a few extremists who are really anti-medicine but they are in the minority," she says, "To me it wasn't 'unassisted or else'. If you have good back-up plans - you know the warning signs to watch for and you are really in touch with what is going on - it is safe. I had back-up midwives and knew which hospital I would go to if necessary."

Mary Siever, 36, from Alberta, Canada, has free-birthed three children at home. "I think hospitals and doctors have their place, I just don't think they have their place in birth," she says. "I've noticed a lot more people are getting interested in it now. People are trusting themselves more or maybe they are trusting the doctors in hospitals less. I wanted personal control and responsibility. For others, it may be that they had a horrible experience in hospital and don't want that again."

Bornfree, the biggest internet forum for freebirthers, has more than 1,000 members worldwide, mostly in the US, Canada, Australia and New Zealand. In the past 10 years Laura Shanley has heard from "a couple of dozen" British mothers who want to go it alone and Sarah knows of two others who chose to give birth without assistance.

Although it is never going to be a majority movement, the issue of the over-medicalisation of birth is pushing freebirth on to the mainstream agenda in the US. A slogan war has broken out, with natural birth websites selling T-shirts which read "Pizza boys deliver. Women birth", while the American College of Obstetricians and Gynaecologists gave out bumper stickers at a meeting last year, bearing the opposite message: "Home delivery is for pizza."

Home birth per se is not illegal in North America, but in 13 states there are legal issues for midwives attending home births. Denied the chance of an attended home birth, some women would simply rather do it on their own than go into hospital. "Women who feel they are being shoehorned into hospitals, and who don't like what happens to them when they get there, see freebirth as a viable option," says Tina Cassidy, author of Birth: A History (Chatto & Windus, £12.99), who is based in Boston. "It's a fringe thing but it's a signifier of something bigger: women now feel they have no control in the birth process."

What is telling, says Cassidy, is that there is virtually no historical precedent for this movement: "Since the beginning of time women have turned to other women for help in childbirth. There are one or two very small tribes where giving birth alone is a means of status - but even within those cultures people rush to the woman's side afterwards to make sure she and the baby are OK." That women are considering going it alone is a wake-up call for the medical profession in the US, she says, where one in three births now ends in a caesarean section. "I'm not an advocate for or against freebirth. But you can understand why people would go underground. They think, I'm just having a baby. What is the big deal?"

Because freebirth is such a fringe movement there have been no studies on it. However, a report in the magazine New Scientist recently quoted a survey undertaken in a religious community in the state of Indiana, where there were more than 300 unattended births in the 1980s. The neonatal death rate was calculated as 19 per 1,000 live births, compared with seven per 1,000 for the rest of Indiana.

There is some concern that the number of freebirthers in Britian may rise, because so many women feel their choices over how they give birth are limited, says Beverley Beech, chairwoman of the Association for Improvement in Maternity Services. While the health secretary, Patricia Hewitt, has promised that every woman will be able to choose an attended home birth by 2009, the service is currently a postcode lottery. Plus, the government is planning to introduce new - and prohibitively expensive - insurance requirements for independent midwives who currently provide private backup to women who have found it difficult to arrange an attended home birth on the NHS. "If this law comes in, either [independent] midwives will practise illegally or we will have a lot more women who will choose to give birth alone," says Beech. "We have been having discussions about providing a support group for these women so we can provide somebody to be with them."

Freebirth fans contend that it can be better to be alone anyway. On one blog a woman writes of "the thrill of the catch" - what it feels like to seize your baby emerging from your body. Self-delivery is not necessarily something women should strive for, she adds, but something they should know they are capable of. There is much online discussion about "lotus birth" - when the umbilical cord is not cut but left to disintegrate naturally, usually within three days of birth.

One pioneer of the freebirth movement is Dr Sarah Buckley, a respected Australian GP who lectures on home birth and is described by the French natural birth guru, Michel Odent, as "driving the history of childbirth towards a radical and inspiring new direction". Buckley had her fourth child unassisted at home near Brisbane and writes: "It was a great gift for me, with my medical training, to liberate myself ... from expert thinking."

The movement's unofficial leading light, Laura Shanley, explains: "I look at birth as a sexual creative act and you have to be free to birth in your own time and your own way. Even if you are with a midwife, she has to follow certain rules and your body can't do what it needs to do within its own time."

During her five pregnancies, Shanley shunned all monitoring, including scans. The first indication she had that her second child, Willie, was in the breech position was when she was giving birth at home alone and reached down to feel his feet coming out first. Her fourth child, Nicholas, was born prematurely unassisted at home and died almost instantly from a congenital heart condition. Shanley later sought reassurance that the outcome would have been the same in hospital (she was told that medical intervention would have made no difference).

The controversial NHS doctor who writes an award-winning blog under the pseudonym "Dr Crippen" has proposed that at some future point women will be sued by their (damaged) offspring for having had a home birth (let alone an unattended one). Freebirth advocates argue that a woman's choice of how she gives birth is a human rights issue. They say that most births proceed normally and going to hospital only increases the chances of intervention and complications. Even during a home birth, a midwife can intervene in a way the mother doesn't agree with. Is this a selfish attitude? Not necessarily, says Cassidy: "I don't buy that 'selfish' thing. I've heard horrible stories of women haemorrhaging to death in hospital and babies' faces being cut with scalpels during C-sections.

"Women have been giving birth since the beginning of time and birth is very rarely complicated. So is it selfish to stay at home? Or is it selfish to go to hospital?"

My story: 'I shed the placenta and had a bath with my son'

I always planned to have children but I could never imagine giving birth in a hospital, or with any kind of official in attendance. The only way I had ever been able to picture myself giving birth was alone, or with an old crone in silent attendance. At night in the woods by a stream was my preference, but my own front room and bath was, when my time came, the best available option.

As the day approached and pressure from the NHS to "plug-in" mounted, my partner became increasingly fearful and I increasingly resolute. Talk of stillbirth - designed to drive me to hospital - only heightened my distrust of those who saw fit to try and worry me at such a vulnerable time. I had, by this time, had my fill of the local midwives, all but one of whom had treated me with a complete lack of empathy, and the idea of inviting a random team of two of these frankly cold women into my small home seemed laughable.

The evening before I went into labour I had my spirits boosted by the book Spiritual Midwifery, not because I felt in any way connected to the free-loving, be-necklaced and hairy-partnered women pictured within, but because the pages and pages of homebirth statistics in the back made for optimistic reading. I read the book in the bath before going to bed and went to sleep thoroughly optimistic, When I got up in the night I found a trace of blood, which convinced me my labour had begun. I got up and while I was running a bath, I spread all the lovely white sheets the midwives had provided over the floor in the front room. My contractions were minutes apart within the hour and as the pain quickly intensified I woke my partner, who went straight back to bed on the basis that it would be a "busy day tomorrow". I was soon oscillating between agony and ecstasy, with only time to stagger the five yards between bath and white sheets, at which time I started to panic that I didn't know where my much-read-about cervix was.

I woke my partner, who went out looking for a newly qualified midwife who happened to be staying with a neighbour, and he returned with a drunk woman who reeked of cigarettes, which put me right off my contractions. I sent her away after agreeing with the general consensus that I was unlikely to give birth until the following day. As soon as she left I felt the baby's head emerging, and after much screaming but less than four hours of labour I gave birth to a very skinny boy on some very bloody sheets. I painfully shed the placenta and had a bath with my son before going back to bed. He is now four, and fine, and very wonderful, by the way.

In my second pregnancy I avoided all contact with the NHS and had no antenatal care whatsoever. After 10 hours of extremely painful labour at home, alone throughout, I gave up and called an ambulance. Less than an hour later, on my back in hospital, I gave birth, vaginally, to premature twins. In terms of the amount of medical intervention I had to have, it was the opposite of my hopes and dreams, but I had never imagined having twins - and what a lovely surprise that was. Besides, dialling 999 was always my back-up plan, being only 10 minutes from the nearest hospital. The twins are now big and bonny.
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