The U.S. Food and Drug Administration (FDA) lists valproic acid and other forms of valproate in Pregnancy Category D. This indicates that there is clear evidence of risk to the baby, but the benefits may outweigh the risk for pregnant women who have a serious condition that cannot be treated effectively with a safer drug.

The babies of women taking valproic acid have an increased risk of minor defects of the face or head, developmental delay, or deformities affecting the arms, legs, or organs. The risk of defects is higher for women who take more than one seizure medicine and for women with a family history of birth defects.

Women who are capable of becoming pregnant should take at least 400 mcg (0.4 mg) of folic acid (folate) daily to help prevent a type of birth defect called a neural tube defect. (The best-known of these is spina bifida, in which the spinal cord is not completely enclosed.) These defects are estimated to affect at least 1-2% of infants whose mothers took valproic acid early in their pregnancy. This figure may be higher than for some other seizure medicines. Women at high risk, such as those with a history of this kind of defect in a previous pregnancy, should take 4000 mcg (4 mg) daily, beginning before they become pregnant. Whether folic acid is effective in preventing defects related to valproic acid has not been proven, however, so the doctor may recommend a check-up using ultrasound during the 18th to 20th week of pregnancy.

Taking high doses of valproic acid and having especially high levels in the blood seem to increase the risk of some defects. Preventive measures may include:

• using a different seizure medicine


• taking less valproic acid (with the doctor's OK)


• taking smaller doses of valproic acid more times each day (or taking extended-release Depakote ER) to avoid large fluctuations in blood levels

About 20% to 35% of women have seizures more often during pregnancy because of changes in hormones or changes in how medicines are handled by the body. The doctor may recommend frequent blood tests to check the level of valproate in the blood. Then the amount taken can be adjusted as needed.

Breast-feeding by mothers taking valproic acid should be safe for healthy, full-term newborns, although a small amount (3-5%) of the medication will appear in the milk. The amount the baby gets is less than 6% of the lowest dose that a doctor might prescribe for a baby with seizures.