Usage in Pregnancy: According to published and not published reports, valproic acid may produce teratogenic effects, such as neural tube defects (e.g. spina bifida) in the offspring of human females receiving the drug during pregnancy. There are data that suggest an increased incidence of congenital malformations associated with the use of valproic acid during pregnancy when compared with some other antiepileptic drugs. Therefore, valproic acid should be considered for women of childbearing potential only after the risks have been thoroughly discussed with the patient and weighed against the potential benefits of the treatment. There are multiple reports that indicate that the use of antiepilepsy drugs during pregnancy results in an increased incidence of birth defects in the offspring. Therefore, antiepileptic drugs should be administered to women of childbearing potential only if they are clearly shown to be essential in the management of their disease.
The data described as follows were gained almost exclusively from women who received valproate to treat epilepsy. The incidence of neural tube defects in the fetus may be increased in mothers receiving valproate during the first trimester of pregnancy. The United States Centers for Disease Control (CDC) has estimated the risk of valproic acid exposed women having children with spina bifida to be approximately 1 to 2%.
Other congenital anomalies (e.g. craniofacial defects, cardiovascular malformations and anomalies involving various body system), compatible and incompatible with life, have been reported. Sufficient data to determine the incidence of these congenital anomalies are not available.
The higher incidence of congenital anomalies in antiepileptic drug-treated women with seizure disorders cannot be regarded as a cause and effect relationship. There are intrinsic methodological problems in obtaining adequate data on drug teratogenicity in humans; genetic factors or the epileptic condition itself, may be more important than drug therapy in contributing to congenital anomalies.
There have been reports of developmental delay, autism and/or autism spectrum disorder in the offspring of women exposed to valproic acid during pregnancy.
Patients taking valproate may develop clotting abnormalities. A patient who had low fibrinogen when taking multiple anticonvulsants including valproate gave birth to an infant with afibrinogenemia who subsequently died of hemorrhage. If valproate is used in pregnancy, the clotting parameters should be monitored carefully.
Hepatic failure, resulting in the death of newborn and of an infant, has been reported following the use of valproate during pregnancy.
Tests to detect neural tube and other defects using current accepted procedures should be considered a part of routine prenatal care in childbearing women receiving valproate. Antiepileptic drugs should not be discontinued abruptly in patients in whom the drug is administered to prevent major seizures because of the strong possibility of precipitating status epilepticus with attendant hypoxia and threat to life. In individual cases where the severity and frequency of the seizure disorder are such that the removal of medication does not pose a serious threat to the patient, discontinuation of the drug may be considered prior to and during pregnancy, although it cannot be said with any confidence that even minor seizure do not pose some hazard to the developing embryo of fetus.
Nursing Mothers: Valproate is excreted in breast milk. It is not known what the effect this would have on a nursing infant. Consideration should be given to discontinuing nursing when valproic acid administered to a nursing woman.