Test could predict which mothers will need Caesareans

The test is designed to establish which mothers could have a vaginal birth and who may need a C-section

A test which could stop women labouring for hours in the hope of a "normal" birth only to end up with a Caesarean section has been developed in Sweden.

Researchers have established that when high levels of lactic acid are measured in the amniotic fluid, it is unlikely the mother will deliver vaginally.

Measuring this acid could help decide whether to end a difficult labour and opt for a Caesarean earlier.

The test is being rolled out in a number of European hospitals.

Prolonged labours which end up in a Caesarean section are seen by many as the worst of all worlds.

In the UK, despite the mantra "too posh to push" more than half of Caesareans are emergency rather than elective procedures, in which the mother frequently undergoes a long and painful labour before an urgent operation is deemed necessary to protect the health of both her and her baby.

Running on empty

The test was developed by the Swedish company Obstecare on the back of research led by Liverpool University and Liverpool Women's Hospital.

Their studies showed that the uterus produces lactic acid as other muscles do when they work hard, but that when it reaches a certain level the substance starts to inhibit contractions.

The hormone oxytocin is usually administered in cases of slow labours to stimulate the uterus into contracting, but not all labouring women respond to it.

Johan Ubby of Obstecare says the test should help doctors establish which women may go on to deliver vaginally, as low levels of lactic acid suggest the uterus could still produce the contractions needed to push out the baby.

"But a high level of lactic acid in the amniotic fluid indicates that the uterus is exhausted. To stimulate this kind of labour with an oxytocin infusion would be like asking a marathon runner to run an extra 10,000 metres after he or she has passed the finish line."

He says the system of testing, which has already started in hospitals in Sweden, Norway and Belgium, should reduce the number of Caesareans for women who may not need them and accelerate them for those that do to "avoid the risk of complications from a long birth and limit unnecessary suffering".

Professor Donald Peebles, a spokesman for the Royal College of Obstetricians and Gynaecologists and consultant at University College, London, described the test as a "nice idea".

"I can definitely see the logic, and it would be straightforward to carry out. I would be interested in seeing a large prospective study where you could see the impact it had on the management of labour and whether overall outcomes were improved."

Professor Susan Wray of the Centre for Better Births added that one next step would be to work out how to "wash away" the acid which appears to inhibit labour.

"Prolonged labour occurs in one in 10 births and it's particularly a problem for first time mums. The truth is there has not been a new drug to treat problems in labour for 60 years - pharmaceutically, there's been nothing new since oxytocin.

"It's high time for this to move up the agenda. We simply do not always give women's health the priority it deserves."