Researchers have found that caffeine may be linked to the development of epileptic discharges in cells from newborn mammals that have been briefly starved of oxygen.

The levels of oxygen that reach a baby often dip during birth.

It has been established that caffeine contained in coffee drunk by pregnant women crosses into the brain of the developing foetus.

A research team from the Institut National De La Sant� in France examined cells from the hippocampus, a part of the brain that is thought to control memory.

They subjected the cells to the same level of caffeine found in several cups of coffee, and starved them of oxygen for three to four minutes.

They found that the cells all fired at the same time - a phenomenon seen during epileptic seizures.

Nothing happened if caffeine was not added to the preparation, or if oxygen was present.

Stress chemical

Babies can be starved of oxygen at birth

The researchers believe that the caffeine molecules bind to receptors in the cells, blocking the action of a chemical called adenosine which plays an important role in handling stress.

During stressful episodes such as oxygen starvation, adenosine protects the nerve circuits from uncontrolled activity.

Caffeine is routinely given to premature babies to suppress the breathing disorder apnea.

A drug similar to caffeine, theophylline, is used to treat patients with certain types of asthma.

The researchers are to investigate the potential adverse effects of these two drugs in unborn babies.

Professor John Duncan, medical director of the National Society for Epilepsy, said it was well established that babies who had been starved of oxygen were more vulnerable to developing epilepsy.

He said that it was feasible that caffeine could exacerbate the symptoms.