Exposure to valproate during pregnancy can impair a child's cognitive development

Apr 15, 2009

Three-year-olds whose mothers took the antiepileptic drug valproate during pregnancy had average IQs six to nine points lower than children exposed to three other antiepileptic drugs, a landmark multi-center study has found.

The study's authors say that women of childbearing age should avoid valproate as a first choice drug for the treatment of . The results are published in the April 16, 2009, issue of the .

The Neurodevelopmental Effects of Antiepileptic Drugs (NEAD) study is following more than 300 children born to women with epilepsy between 1999 and 2004. Investigators at 25 epilepsy centers in the United States and the United Kingdom are participating. At enrollment, the women were taking a single antiepileptic agent: carbamazepine, lamotrigine, phenytoin or valproate.

The NEAD study previously found that valproate exposure also increases the risk of anatomical birth defects, even though it was not designed to look for them.

"There are clear risks associated with valproate, and physicians have an obligation to inform women about them," says lead study author Kimford Meador, MD, professor of neurology at the Emory University School of Medicine. "Valproate still has an important role in treating epilepsy, because some patients' seizures can only be controlled with valproate. However, we are recommending that women with epilepsy try another drug first."

Around 15 percent of patients with primary generalized epilepsy respond only to valproate, but this selectivity does not apply to other forms of epilepsy, Meador says.

Meador stresses that women who are pregnant and take valproate should not stop without consulting a physician, to avoid seizures with potentially serious consequences.

Valproate's effects on child IQ appear to be dose-dependent, so it may be possible to reduce risk by taking it in lower doses more frequently or in a sustained release formulation, Meador says.

A child's IQ is usually strongly influenced by the mother's IQ. Out of the four antiepileptic drugs studied, only valproate disrupted this relationship.

Preliminary results describing the children's IQs at 2 years of age were reported at the end of 2006. The studies' findings were strengthened by researchers' ability to include more children and measure their progress after three years. The researchers plan to follow the children until age 6.

Valproate is also prescribed for bipolar disorder and migraine headaches. It is sold under the brand name Depakote. Last year the FDA approved a generic version.

More information:

Meador, K.J. et al. Cognitive function at 3 years of age after fetal exposure to antiepileptic drugs N Eng J Med 360: page numbers? (2009).

Meador K.J. et al. In utero antiepileptic drug exposure: fetal death and malformations. Neurology 67: 407-412 (2006)

Source: Emory University (news : web)

Explore further: Researchers find unsuspected characteristics of new CF drugs, offering potential paths to more effective therapies

add to favorites email to friend print save as pdf

Related Stories

Lower IQ found in children of women who took epilepsy drug

May 03, 2007

Children of women who took the epilepsy drug valproate during pregnancy appear to be at a greater risk for lower IQ, according to research presented at the American Academy of Neurology's 59th Annual Meeting in Boston, April ...

Epilepsy drug may increase risk of autism in children

Dec 01, 2008

A new study shows that women who take the epilepsy drug valproate while pregnant may significantly increase their child's risk of developing autism. The preliminary research is published in the December 2, 2008, print issue ...

Epilepsy drug may increase risk of birth defects

Jul 21, 2008

Taking the epilepsy drug topiramate alone or along with other epilepsy drugs during pregnancy may increase the risk of birth defects, according to a study published in the July 22, 2008, issue of Neurology, the medical journa ...

Epilepsy drug causes bone loss in young women

Apr 28, 2008

Young women who took the commonly used epilepsy drug phenytoin for one year showed significant bone loss compared to women taking other epilepsy drugs, according to a study published in the April 29, 2008, issue of Neurology, the me ...

A child's IQ could be affected by maternal epilepsy

Sep 11, 2007

A history of maternal epilepsy and its associated treatment may be linked to impaired intelligence later in life, says a new study published in Epilepsia. Dr. Nina Oyen, M.D., of the University of Bergen and Norwegian Institute ...

Epilepsy drugs may cause sexual disorders

Oct 24, 2007

The use of antiepileptic drugs (AEDs) can lead to decreased fertility and increased incidence of reproductive endocrine disorders in both men and women. A new study published in Epilepsia investigates the effects of withdrawal ...

Recommended for you

Strategy proposed for preventing diseases of aging

11 hours ago

Medicine focuses almost entirely on fighting chronic diseases in a piecemeal fashion as symptoms develop. Instead, more efforts should be directed to promoting interventions that have the potential to prevent ...

User comments : 0