Epilepsy drugs pregnancy warning

Epilepsy drugs are linked to developmental problems

Some epilepsy drugs taken during pregnancy may impair children's normal brain development, say researchers.

Around one in three people taking anti-epileptics is a woman of reproductive age.

It is estimated that one in 250 pregnancies will be exposed to anti-epileptic drugs.

There are risks to a pregnancy from taking anti-epileptics but there are also risk from having seizures

Professor David Chadwick, Walton Centre for Neurology

Researchers carried out a survey of women who were registered with the Mersey Regional Epilepsy Clinic.

They found that children whose mothers had taken anti-epileptic drugs during pregnancy were 50% more likely to have "additional educational needs" than those whose mothers had not taken these drugs.

Children whose mothers had relied solely on the commonly prescribed anti-epilepsy drug valproate during pregnancy were three times more likely to have additional educational needs.

Those whose mothers had taken a combination of drugs, including valproate, had over twice the risk.

Another commonly prescribed drug Carbamazepine was not associated with an increased risk when taken alone.

The authors emphasis that more than nine out of 10 pregnancies in women with epilepsy are not problematic.

But they say there is growing concern over the risks of developmental delay in children whose mothers take drugs for epilepsy.

Prospective mothers need to be informed in particular about the risks associated with valproate.

Seek advice

Lead researcher Professor David Chadwick of the Walton Centre for Neurology, Liverpool, told BBC News Online that women with epilepsy should seek expert advice from a doctor with specialist knowledge of the condition before seeking to get pregnant.

There is increasing evidence to suggest that wherever possible woman of child bearing potential should avoid valproate

Dr Tim Betts, British Epilepsy Association

He said: "There are risks to a pregnancy from taking anti-epileptics but there are also risk from having seizures.

"It is absolutely vital to try to get good quality information to women on the relative risks, which vary enormously between individuals."

Professor Chadwick said more neurologists with specialist knowledge of epilepsy were badly needed in the NHS.

His team is now working to establish whether other factors are partly responsible for the apparent link between epilepsy drugs and delayed development. They also hope to quantify the impact of the drugs.

Dr Tim Betts is medical advisor to the British Epileptic Association and runs a pre conception counselling clinic at Birmingham University Seizure Clinic.

He told BBC News Online: "Most pregnancies that are problematic could probably be avoided by careful preconception counselling geared towards a proper risk assessment in the light of present knowledge and the careful withdrawal of high risk drugs like valproate, substituting drugs thought to be safer where necessary.

"There is increasing evidence to suggest that wherever possible woman of child bearing potential should avoid valproate.

"This research is important as it confirms clinical suspicions that many of us have long held and confirms our clinical practice here."

Research published earlier this year suggests that pregnant women with epilepsy do not receive proper care from their doctors.

A team from the Royal Victoria Infirmary in Newcastle found that doctors were failing to give women with epilepsy proper advice about the risks associated with their condition.

For instance, epilepsy is associated with an increased risk of spina bifida.

Data from a three year period to 1996 shows that 19 women died during pregnancy from epileptic seizures after coming off their medication.

Valproate is given to around a third of women with epilepsy who have a genetic form of the condition known as idiopathic generalised epilepsy.

The research is published in the Journal of Neurology Neurosurgery and Psychiatry.