Teratology of valproic acid: an updated review of the possible mediating mechanisms.

Valproic acid (VPA) is an anti-epileptic drug (AED) which is currently being investigated for its potential application in the treatment of several types of cancers, including solid and non-solid tumor. It is well-known that prenatal exposure to VPA largely increases the risk for malformations and other developmental disorders. This review concentrates on clinical and experimental data on congenital anomalies attributed to maternal VPA exposure. Particular emphasis is placed on the potential mechanisms underlying VPA-induced malformations. Although several mechanisms have been suggested, there appears to be no data in the literature in support of a single definitive mechanism for VPA-exposure-related fetal malformations.