Quite unintentionally, old neighbours Rachel Scott and Léonie Ainapore have found themselves conducting a little social experiment with their children. When they had their first babies, in 1999, they automatically adopted the best liberal, child-centred practice: breast-feeding on demand (sorry, "request"), babyslings, co-sleeping, the lot. While pregnant, Scott, now 36, had been enthralled by Deborah Jackson's paean to co-sleeping, Three in a Bed; Ainapore, 32, who had never so much as changed a nappy, assumed that maternal instinct would kick in. But demand-feeding round the clock did nothing to soothe Ainapore's baby's colic, while Scott's son was still waking twice nightly after a year. As they found their lives descending into chaos, they began to feel badly let down by a philosophy which they had been told by everyone - from midwives to magazines - was the best, indeed the only, way to be a parent.

"You're constantly being told about mothers who wear their babies and sleep with them," says Ainapore, "and I thought if I just loved and nurtured him, and slept with him, he would be OK. But I was constantly at his beck and call, and he wasn't contented - I was exhausted and felt a failure."

No one mentioned the possibil ity of establishing a routine. "There were just these goals - your baby will be sleeping through by four months - that we never seemed to make."

So it is that with their second babies, born a few months ago, both women have put them on a rigorous schedule of timed sleeps and feeds from their earliest weeks; they are kept awake as much as possible during the day, and left to settle themselves at night.

It may have taken a generation, but every official bit of advice given to new parents toes the child-centred line. When, after three sleepless nights in hospital, Ainapore wanted the midwives to take her baby for a couple of hours so she could rest, she was told in an astonished tone: "'No, we prefer our mothers to bond with the babies.'"

The advances in child psychology of the 1960s and 70s, which revealed the importance of early stimuli and intimacy, combined with feminism to inspire such gurus as Miriam Stoppard, Penelope Leach and Sheila Kitzinger in the idea that birthing practice and babycare needed to be liberated from a medical system still preoccupied with sanitation, routine, hierarchy and efficiency. But now that their ideas are firmly established in the mainstream, and hospitals no longer whisk newborns off to the nursery or enforce five-hourly bottle feeds, many new parents aren't finding their job any easier or more rewarding.

More recently, there has been something of a rebellion - and some serious moaning about the martyrdom of modern motherhood - from Rachel Cusk, Kate Figes and Kate Mosse, et al, as well as terrifying TV programmes on "damage limitation" methods, from toddler-taming to controlled crying. And where the state (in the form of nurses, midwives and health visitors) has failed, nanny beckons, with her sweet strictures and reassuring rules. Celebrity-endorsed maternity nurses such as Tracy Hogg (author of Secrets of the Baby Whisperer) and Gina Ford are in enormous demand.

"The one, and perhaps the only, good thing about Ford," explains Scott, "is that she gives you a pre-emptive concrete plan, which takes into account how one element of the day affects another. It puts you in control, and shifts the whole power relationship."

Despite blanket condemnation from the established experts for its practical heresies and hectoring tone, Ford's Contented Little Baby Book has been a huge word-of-mouth success, selling over 200,000 copies and spawning its own alternative support groups. A new edition is out this month, together with an additional step-by-step tome on how to wean later in the year. Also out in June, psychologist Dorothy Einon's Golden Rules of Parenting (there are 100, apparently) promises to "do for child rearing what Ford did for the world of babies".

Are we simply seeing a backlash against liberal parenting, and were the traditionalists right all along? (Make baby eat her greens and put her to cry at the bottom of the garden.) Or is the break-up of the consensus a sign of renewed debate, potentially offering a "third way" to parents?

On a purely practical level, the determined non-authoritarianism of liberal parenting seems to have left a vacuum of information which foundering parents simply can't tolerate. Confronted with small unhappy babies, Scott and Ainapore found the advice of the babycare books, with their mights, coulds and maybes, impossibly vague. In the drive to emphasise the individuality of each child, it seems some universal physical basics have not been explained to mothers.

"It's very strange that we're not told babies' physical requirements," says 32-year-old new mum Helen Staniland, who put her daughter Daisy on Ford's routine at two weeks old after enduring 10-hour feeds. Ford's book is the only place she has seen concrete information on the amount of sleep a baby needs a day and how much milk its stomach can hold: "Even on the baby milk carton, it says demand-feeding is best. I think it's just a ploy to sell more milk."

There's also a sense that the balance of power has swung too far in the child's favour. "I wouldn't have a relationship with an adult which was just one way," believes new dad and Gina-fan Mike Torrance, 38, "so how can it be healthy for the demands of a little baby to rule you as an adult?"

The case for the child-centred approach has perhaps been overstated to get the message across. In a country where over 60% of mothers give up breastfeeding after six weeks, it is mercilessly talked up to novice parents. One midwife told Staniland: "Your routine sounds good, but we have to say 'demand-feeding' and we have to say 'breastfeeding'."

"The official advice now is that babies get into their own routine," explains Ford, who sees her role as "picking up the pieces". "Well, some babies do, but a great many don't. It's also a political thing: there's not the money to support mothers properly, so they're told to go home and use their natural instincts. Midwives are so overworked they don't have time to outline a more detailed approach.

"I think the tide has turned because the majority of babies are not happy on demand-feeding and mothers can't cope. Imagine being up four times a night with a one-year-old and then being made to feel a bad mother because you can't cope."

Heather Neil, a tutor for the National Childbirth Trust, feels the backlash is due to people still being misinformed about central liberal tenets such as demand-feeding. "For instance, Ford doesn't realise that breastfeeding is a relationship between a mother and her baby, not just a way to get milk into it," she says. "I understand that some people are desperate to get their nights back, but the price you pay for following her methods is listening to your baby cry. Of course, you can train babies. If their needs are not met, they will stop asking."

Backlash is too simple a term for what's happening, believes Dorothy Einon, a senior lecturer in psychology at University College London. Another wave of advances in psychology, this time in the fields of evolution and learning, is refining our ideas about what happens when you let a child cry.

"A lot of what's going on now is underpinned by basic learning principles," she say. "For instance, children won't put themselves to sleep if they don't learn to. I do think the tendency to go back to Truby King-style feeding programmes will swing back again because it simply doesn't work with some children. It worked when we were giving children bottles of con densed milk, but not with breastfeeding. I don't overlap completely with Ford, but we share the basic principle of reward. If you reward a child, it will respond - even if you, or it, is unaware of what you're doing."

A shift in attitudes, which she dates from the mid-80s, has also played its part. "Society as a whole became more controlling, and the 60s children started having their own children, who turned out to be much more conventional." The rise of the dual-income family, where mothers go back to work a few months after birth, has also necessarily made parents more pragmatic - "whereas the 60s earth mother approach was what baby wants, you give. There's also a realisation that you're raising a child for the world out there and they have to learn to share, too."

Sheila Kitzinger, whose new book Birth Your Way sits firmly in the liberal tradition, points the finger at "a so-called 'post-feminist' self-centredness which says you've got a right to your own life and don't let your kids get any power over you". She recognises a demand for instruction: "Publishers commission 'how-to' books and say that women want clear, numbered instructions these days. They're looking for a kind of Delia Smith of child-rearing. I find that daunting - because I don't think life is like that."

What we're seeing, according to Jackson, is "not so much a backlash as an enormous growth in awareness that there are different ways to do things. People are still buying Three in a Bed in enormous numbers, so they're not all doing Gina Ford. It's a very exciting time because there are more voices on the babycare shelves than there have ever been before."

Baby Wisdom, her new book on global approaches to the first year of parenting, also published this month, draws on the new field of ethnopaediatrics opening up in the US. This looks at anthropology and the history of childrearing and will, she hopes, replace the authoritarian, clinical model of childrearing advice.

The way to truly empower parents is to give them the full range of information, "otherwise you end up following the book, not the baby", says Jackson. Her comparative approach is to be tolerant: "Because we're not all going to make the same choices. In order to get back to the idea of community, in which childrearing is a neighbourhood watch activity, we've got to reach the point of tolerance, because we're just not going to have community with consensus any more."

· The New Contented Little Baby Book, by Gina Ford (Vermillion, £9.99); The Contented Little Baby Book of Weaning (Vermillion, £9.99, June); Birth Your Way, by Sheila Kitzinger (Dorling Kindersley, £9.99); Baby Wisdom, by Deborah Jackson (Hodder, £14.99); The Golden Rules of Parenting, by Dorothy Einon (Vermillion, £6.99)