When Jodie Lewis was born two months prematurely, her doctors privately doubted she would survive. The odds were stacked against her. She weighed just over 2lb and was unable to breathe without the aid of a ventilator. For four months her parents kept vigil by her incubator in the intensive care unit. Only then were they able to hold their baby in their arms.

That was two years ago, but the nightmare of having another premature baby loomed large when Helen Lewis, 30, discovered in February that she was pregnant with twins. 'Jodie had a bad start and we went through hell, but we decided we would still try for another baby,' Mrs Lewis says.

Having already had a pre-term birth, her risk of delivering early increased five-fold, Mrs Lewis's doctors told her. 'I had mixed feelings when I found out I was pregnant again. On the one hand I was very happy, but I also expected that things wouldn't turn out to be normal,' she says.

But Mrs Lewis has been receiving special attention at the hands of a team of Leicester scientists and doctors who have set up the first pre-term birth clinic devoted to women at risk of giving birth prematurely. She is one of 50 women to benefit from the more focused care offered in the clinic at Leicester Royal Infirmary. As well as the full range of routine antenatal care, these women also undergo regular bacterial screening since infections, which cause half of premature births, can easily be eradicated by antibiotics if detected early.

About 18,000 babies are born before 34 weeks' gestation in the UK every year - after this length of pregnancy most babies will survive. There is now mounting evidence that low birth weight, a consequence of prematurity, is linked to a number of serious health problems, such as heart disease, in later life. There is also evidence that low birth-weight babies are more likely to have learning difficulties. 'The consequences for the child born prematurely and for the family are enormous,' says David Taylor, professor of obstetrics and gynaecology at the Leicester Royal Infirmary. 'A lot of these babies end up with severe handicap, such as cerebral palsy, and that's a legacy for life.'

Despite better obstetric care, the rate of pre-term birth has remained largely unchanged for decades. The fundamental causes are not well understood. When labour begins too early, all doctors can do is give drugs to suppress it and steroids to promote development of the baby's immature lungs. Pioneering work in Leicester is now paving the way towards the first real hope of detecting and, perhaps, preventing pre-term birth.

A major trial, funded by the Medical Research Council, of antibiotic treatment in pre-term birth is due to start at the clinic in the New Year. 'We don't have time in the routine antenatal clinic to provide women at high risk of giving birth prematurely with the reassurance and education they need about what's going to happen,' Professor Taylor acknowledges.

The clinic is also testing a revolutionary kit which, its makers claim, can predict which mothers who have early contractions will go on to give birth prematurely. Only half will do so but doctors cannot identify them. This results in an enormous waste of resources: looking after women with false symptoms of early birth costs the health service at least pounds 50m a year, including the cost of labour-suppressing drugs that are given unnecessarily.

Although the test was developed by a Californian company, Leicester scientists did the research. The pounds 25 test kit measures levels in the mother's vagina of foetal fibronectin, a protein that is a component of the membrane surrounding the baby in the womb. If foetal fibronectin protein is present in the vagina between weeks 24 and 34 of pregnancy it indicates that the intricate process of rupture has already begun and that the mother is likely to deliver within two weeks - or so its makers claim.

Steve Bell, the Leicester clinic's scientific director, explains: 'Imagine that the membrane surrounding a baby is held together by scaffolding. We discovered that this scaffolding starts to break down, releasing proteins weeks before the membrane finally ruptures in both pre-term and full-term births. This means that we have a window of opportunity from the time this process begins to the time when contractions would have started.

'With this information we can give preventative drugs or prepare a woman mentally for a pre-term birth. Giving the drugs when contractions begin is like trying to push a cork back into a champagne bottle.'

At Leicester, full clinical trials are now under way to test the kit's predictive accuracy. Results should be available at the end of next year. If the kit does prove highly predictive it will also enable scientists to study prevention strategies for those women who are truly at risk of giving birth prematurely.

Dr Bell believes that the chain of chemical events leading to membrane rupture could begin as early as six weeks into pregnancy. He and his colleagues are now working on identifying other membrane materials that come away earlier in pregnancy. Ultimately, they hope to pinpoint the very first protein to signal that the foetal membrane is going to rupture. The benefits would then be two-fold: a kit could be developed that predicts a premature labour even earlier in pregnancy than the foetal fibronectin test and drugs could be designed to inhibit this premature membrane breakdown.

'The future is looking much brighter for women at risk of giving birth early,' Dr Bell says. 'It is only a matter of time before these women will be able to have a simple test to inform them that they are likely to go into premature labour. They can then be given a tampon coated in a drug that will prevent it happening.'

A week ago today, Mrs Lewis gave birth to two healthy daughters, Samantha, 6lbs 12oz, and Jessica, 6lbs 7oz. Her pregnancy was induced at 38 weeks, when she had a Caesarean section. All are doing well.

(Photograph omitted)