WASHINGTON -- The FDA has issued a statement reminding patients and doctors that valproate sodium, valproic acid, and divalproex products increase the risk of birth defects in babies exposed to the chemicals during pregnancy.
The medications -- used to treat epilepsy since 1978 and more recently for bipolar disorder and migraine -- can cause neural tube defects, craniofacial defects, and cardiovascular malformations in unborn children during the first trimester. This is often before many women know they are pregnant, the FDA said in a statement.
Use of the products increases neural tube defects during the first 12 weeks of pregnancy from one in 1,500 to one in 20, on average, the FDA noted.
Babies born to women taking valproate for epilepsy are more than three times as likely to have birth defects as those born to women on a different therapy (10.7%, 95% CI 6.3% to 16.9% versus 2.9%, 95% CI 2.0% to 4.1%), according to data from the North American Antiepileptic Drug Pregnancy Registry.
The FDA cautioned women of childbearing potential to take valproate only if it is essential for managing a medical condition. Those taking the drug who are not planning pregnancy should use contraception, the agency said.
The agency is now requiring a patient Medication Guide for each antiepileptic drug, including valproate, explaining the risks and benefits.
Women planning to become pregnant can reduce the risk of congenital neural tube defects by taking folic acid before and during the first trimester of pregnancy, the FDA noted.
The agency also noted a danger to pregnant mothers and their child if epilepsy or bipolar disorder is left untreated while the baby is developing. Likewise, it reminded doctors and patients of a major risk associated with ceasing valproate therapy suddenly.
The FDA recommended that women talk with healthcare professionals before stopping use of valproate products if they become pregnant.
It also recommended women who become pregnant while taking valproate or other antiepileptic drugs enroll in the North American Antiepileptic Drug Pregnancy Registry to help gather more information on the safety of the medications during pregnancy.