Although valproate in pregnancy has been previously linked with congenital malformations, a ten-year Danish study revealed yet another reason why women might avoid use of the popular epilepsy drug. According to Medscape, researchers found that women who take valproate during pregnancy are three times more likely to have a child with an autism spectrum disorder and five times more likely to have a child with profound childhood autism when compared with unexposed children.
Also known by its commercial name, Depakote, valproate is used for the treatment of epilepsy and other neuropsychological disorders. The drug has been previously associated with low intelligence in children who were exposed during pregnancy, and it also increases the risk of malformations. Although valproate may be the only treatment option for women of childbearing potential, researchers speculated that prenatal exposure to the drug may increase the risk of autism.
Denmark researchers conducted a study of 655,615 children born in Denmark from 1996 through 2006. With the use of national registries, they were able to determine that 5,437 children were identified with autism spectrum disorder, including 2,067 with childhood autism. During their pregnancy, 508 women took valproate. Even after adjusting for parental age at conception and psychiatric history, gestational age, sex, and other potentially confounding factors, the risk of autism for valproate-exposed children remained elevated.
While past use of the drug did not raise a child’s risk of being diagnosed with autism spectrum disorder, its use by a woman during pregnancy resulted in an absolute risk of 4.42 percent that the child would receive such a diagnosis at some point in his or her early years. When the child’s mother took valproate during pregnancy, the absolute risk of childhood autism diagnosis, which is generally a more disabling condition, was 2.4 percent.
Although the increased risk seems small, these numbers are significant. According to the study that was published in The Journal of the American Medical Association, “because autism spectrum disorders are serious conditions with lifelong implications for affected children and their families, even a moderate increase in risk may have major health importance.”
For women of childbearing age with epilepsy, the elevated risk of autism development in their child should be weighed against the important of managing their condition. Dr. Jakob Christensen, who led the study, notes that women who may become pregnant certainly should discuss possible alternative treatments with their doctors, as knowledge is key to making these decisions: “There must be a continuous effort to include this information along with all the other risks in discussions with women of childbearing age who are candidates for valproate.”