The lives of hundreds of babies could be saved every year thanks to a simple 15-minute blood test developed at an NHS hospital, which is set to revolutionise the way doctors treat pre-eclampsia - a serious condition that severely affects two in every 100 pregnant women.
Described as "one of the great unsolved mysteries of medical science", pre-eclampsia is a severe type of high blood pressure which can lead to fits that can be fatal for mother and baby.
The only way to cure it is to deliver the baby. Thousands of babies have to be delivered early to prevent the condition worsening and hundreds die because of the complications of an early birth. In the UK, around 1,000 new-born babies die because of pre-eclampsia every year. It also causes the deaths of six to seven women each year.
Until now, the only way to diagnose the condition has been to check for high blood pressure and measure protein levels in urine, but both tests are unreliable, meaning that the condition is often missed. Doctors also have no clear way of telling how severe the condition is, leading to thousands of precautionary - and risky - early deliveries.
But a new test, developed by researchers at London's Guy's and St Thomas' Hospital, was found to identify 96 per cent of women who had the condition and needed their baby to be delivered within two weeks.
The blood test, which gives an accurate result in just 15 minutes, measures the level of placental growth factor (PIGF) in the blood. The results of a study into the test's efficacy showed that women who have a very low PIGF level have severe pre-eclampsia, meaning their baby should be delivered in the next 14 days. But those with a high level are very unlikely to have a severe form of the condition - regardless of their other symptoms - and can safely carry their baby until full term.
The study was published today in the American Heart Association journal Circulation.
Professor Andrew Shennan, a consultant obstetrician at Guy's and St Thomas', who led the study, told The Independent that the new test represented the "most important advance" in obstetrics that he had seen in 20 years of working in the speciality.
"This test tells you in minutes if a person has a disease that matters or not," he said. "It will radically change how we manage these women. It's not expensive and it's more effective than all the other tests that we have combined."
pre-eclampsia affects one in 10 pregnancies, and is severe in around 10 to 20 per cent of cases. It is believed to be caused by problems in the placenta, the organ which connects the baby's blood supply to the mother's.
A UK-wide trial of the blood test is now planned. Professor Shennan said that he had already been in discussions with the Department of Health, and hoped to see the blood test placed on a fast-track for commissioning throughout the NHS.
The breakthrough has the potential to save thousands of lives worldwide if adopted internationally. Professor Shennan said healthcare systems in other countries were watching the trials "very closely".
The study was jointly funded by the baby charity Tommy's and the company which manufactures the test, Alere.
Jane Brewin, chief executive of Tommy's, said: "pre-eclampsia is one of the great unsolved problems of medical science and if it isn't caught early enough, can in the worst cases lead to the death of both mother and baby…This new test could revolutionise pre-eclampsia treatment so that it is spotted quickly, with greater accuracy, and women's health managed so that their baby is only delivered when absolutely necessary - ultimately saving lives."
Gemma Barrett, 32, from Kingston, was kept in hospital for more than a week being monitored for suspected pre-eclampsia. Her condition became serious and she had an emergency caesarean to deliver Sebastian, her first baby, at 33 weeks. Sebastian was not breathing when he was born and had to be resuscitated.
She says: "Being kept in hospital and monitored was very traumatic. I was uncertain about what was happening to me and my baby, as were the doctors. If this test had been available, doctors would have had confirmation that I would develop severe pre-eclampsia and my caesarean wouldn't have been an emergency, which caused huge stress for me and my baby.
"I'm keen to have another baby, but know I'm likely to get pre-eclampsia again. This test would give me confidence that if I did have it, the doctors would know in advance if it was going to be a problem and treat me before it became an emergency."