It was Bono who advised me to take every kind of painkiller I could get my hands on during childbirth (though I'm afraid the story of how I came to be discussing my imminent labour with Bono will have to wait for another occasion). 'My wife's had four,' he said knowingly, when I voiced a naïve and untested faith in the powers of aromatherapy and whale music. 'Why would anyone choose not to have pain relief? That's like choosing to have the flu.'

It's a sensible enough observation. Our grandmothers' generation, gasping their babies out on to the kitchen tiles with not so much as an aspirin for comfort, must have dreamed of a day when advances in medical technology would conspire to take the labour out of labour. According to statistics presented by the All-Party Parliamentary Group on Maternity at the beginning of this month, the rate of 'normal' births - those without induction, caesarian section, assisted delivery or some kind of anaesthetic - in NHS hospitals has fallen by 15 per cent in a decade to an all-time low of 44 per cent, and the caesarian rate has risen to 21.5 per cent for 2000-01. Since post-partum maternal and infant mortality remains rare, why is it that an increasing number of midwives and health care professionals are voicing their concern over these figures, including Dr Michel Odent the French obstetrician who pioneered natural childbirth and waterbirth in the 1970s and has just published a thesis arguing that 'industrialised obstetrics' is responsible for all manner of social ills from autism to teenage drug abuse? Though this 'trend' can't be separated from the problem of resources in the NHS, it is easier for the media to point the finger at celebrities for the part they play. One obstetrician lamented in the Daily Mail last year, 'Why do we not have more stars "coming out" in favour of natural childbirth?'

Well, happily, it seems that now they are. If the well-documented elective caesarians of the likes of Madonna, Zoe Ball and Victoria Beckham gave rise to the tired 'too posh to push' tag, a rival camp appears to be emerging, not yet blessed with its own alliterative label ('too A-list for anaesthetic'? 'too stylish for surgery'?) but including Kate Moss, Sadie Frost and Sharleen Spiteri, who are all shortly to give birth in the Hospital of St John and St Elizabeth, London, a private clinic that promotes natural birth methods; Davina McCall, who had her daughter under the care of The Birth Centre, a similar clinic in south London, and Kate Winslet, who consulted independent midwife and acupuncturist Zita West throughout her pregnancy and has subsequently written the foreword to West's new book.

The natural birth movement is not a new trend at all - in fact its principles are as old as childbirth itself - and where once it was seen as the preserve of wafting earth mothers who suggested imagining yourself opening up like a beautiful flower as you give birth, it is now, despite the statistics, subtly encroaching on mainstream medical practice. Modern methods of hospital delivery may make the business seem more manageable, and perhaps less painful, but in the end it is a false economy, say the advocates of natural childbirth. Having a baby should not be a question of getting something extracted as efficiently as possible, as with a tooth or a dodgy appendix.

The experience of giving birth naturally, without artificial drugs to inhibit the body's normal production of endorphins and hormones, has proven health benefits for both mother and child, enabling the mother to make a much quicker recovery and significantly reducing her chances of postnatal depression. As some commonly used pain relieving drugs can be passed through the placenta during labour, a child born without them is more alert, more likely to be able to breastfeed immediately, thus enhancing the bonding process, and less likely to suffer from respiratory difficulties or other neo-natal complications. 'There is nothing like the way a woman feels after an active birth,' says Janet Balaskas, who founded the Active Birth Centre in north London in the mid-1980s and now runs birth courses for pregnant women and training workshops for midwives. 'There's so much evidence that it's an empowering experience and the best start to being a mother, but it's not being actively implemented in hospitals.' She attributes this to an undeniable shortage of time and midwives in most NHS hospitals, but also to a resistance in attitudes among obstetricians.

'It's a question of changing the atmosphere from one that's predominantly clinical to one that's more intimate, where the mother can feel she's in control of the process, which some obstetricians still see as quirky. In any kind of birth, but particularly in a natural birth, a woman needs one-to-one midwifery support, and I think this is gradually being recognised, but it's important to stress that it doesn't have to be either/or.'

The ideal, in other words, would be to combine the medical expertise of a hospital environment with the comfort of your own front room, and for women who don't want to go all the way to a home birth, the new birth centres provide the best of both worlds. These can be found within the NHS in more progressive areas - the Edgware Birth Centre in west London was established five years ago, and several other London hospitals are in the process of setting up their own - but still the best way to be certain of a midwife's un divided attention and ensure comfort and privacy for your yogic breathing and scented candles is to go private.

'As Recommended in Vogue ' boasts a big purple sticker on the front of The Birth Centre's prospectus, giving some idea of their target clientele. The centre was established by Professor Caroline Flint, a former president of the Royal College of Midwives, and offers one-to-one ante- and postnatal care to clients anywhere within the M25. Women can choose to give birth in their own home with their personal midwives in attendance, or in the centre itself, which has private rooms equipped with birthing pools, showers, sofas and cushions and a masseuse, homeopath and acupuncturist on call. Of their 133 clients in 2001, 107 were normal births, 30 of them in water and only seven women had epidurals for vaginal deliveries. Of these women, 48 per cent gave birth at home, including Davina McCall, who says: 'Having Holly was the best experience of my whole life. I have never felt so fantastic - I wanted to do it all again.'

The Birth Centre's full package, which includes a personal midwife who remains on call to you 24 hours a day including weekends, as well as all scans, blood tests and labour care and a set of birth photographs, will set you back £4,600, but the centre encourages women to view a positive birth experience as an investment, and the prospectus helpfully compares its prices with the cost of a fortnight's holiday, an average wedding or a year's school fees to emphasise the relatively small expense of bringing your child healthy and happy into the world. The Hospital of St John and St Elizabeth charges about £5,000 to see a woman through her first pregnancy and birth, while the Portland, where Liz Hurley and the Beckhams had their children by elective caesarian, charges upwards of £6,000.

Of course, it is entirely possible to have a positive natural birth at home on the NHS, but one of the biggest complaints by the National Childbirth Trust in recent years has been the disparity of maternity units across the country. Pregnant women are entitled to ask for a midwife to attend a home birth, but in reality it will depend on availability and whether the individual hospital has a culture that supports women who want to try.

Rebecca Carter, 33, a publisher from north London, had her first baby, Matilda, at home in a birthing pool with only her husband and a midwife present, and maintains that the intimacy and privacy of her home environment contributed to her confidence in giving birth naturally. 'I was lucky because I had a relatively easy labour,' she says. 'And the midwives were so encouraging when I first suggested a home birth that I was able to go through my pregnancy believing that I could do it.'

Although her only expense was the hire of the birthing pool, she also went to private antenatal yoga and childbirth classes, and feels that education about the process of childbirth, emphasising it as a positive process in which the mother plays an active role, is a significant factor in taking away the dread that so many women feel about the big event.

Balaskas of the Active Birth Centre agrees that the growing interest in a return to natural childbirth is still largely a middle-class phenomenon because the kind of classes that give women enough information to make an informed and confident choice are for the most part provided by independent centres and teachers.

'There are some areas where antenatal yoga and natural birth classes are being funded for free in association with NHS hospitals,' she explains, 'and these projects need to be expanded, because until it is presented as an option that's as widely available as epidurals, the rate of medical intervention in childbirth will continue to rise.'

Perhaps, though, in their own small way, celebrities can begin to exercise a kind of social responsibility by deglamorising unnecessary surgery and provoking a renewed interest in alternative methods of birth. With no disrespect to Bono, in whose words there turned out to be more than a grain of truth.