If it's shown not to be effective, indiscriminate use of the technique will be discouraged

Dr Denis Azzopardi, Imperial College London

Researchers at Imperial College London and the National Perinatal Epidemiology Unit in Oxford have developed a "cooling mattress", filled with water, which they believe will reduce the baby's temperature without discomfort.

They are recruiting more than 200 newborn babies suffering from oxygen deprivation at birth.

Half will have their temperature left as normal, and half will have it reduced by between three and four degrees Celsius for a few days, then slowly restored.

'Standard practice'

The babies will be revisited after 18 months to see if there are any differences between the two groups.

Dr Denis Azzopardi, from Imperial College, is leading the research team.

He said: "If the trial shows that this is an effective treatment for asphyxia, we'll be recommending that baby-cooling should be adopted into clinical practice in the NHS.

"If it's shown not to be effective, indiscriminate use of the technique will be discouraged."

The trial is to be funded by the UK Medical Research Council, and is expected to cost almost �2m - and last a total of six years.

Professor Sir George Radda, chief executive of the MRC, said: "The MRC is pleased to be able to play a part in trying to answer this important issue for babies' health."

One in 500

Asphyxia of newborn babies happens sometimes because the placenta - the blood supply link between the mother and baby - becomes detached or if there is another obstruction to the blood supply.

A quarter of all babies who suffer even moderate asphyxia during birth develop some form of cerebral palsy.

One in 500 babies may suffer from this lack of oxygen during birth.

Other forms of cooling have been attempted, including a water-filled cap which is being tested at two hospitals in Bristol.