Epilepsy is one of the most common neurological diseases in the world. One of the most difficult clinical problems associated with the disease is to treat pregnant women because the use of antiepileptic drugs increase the risk of birth defects in the fetus. The second most common use in pregnant women is an antiepileptic drug valproic acid. Its use is associated with an increased risk of serious birth defects such as neural tube defects, heart defects, cleft palate, urinary tract defects, limb defects, specific syndromes that cause dysmorfizm face or abnormalities of the reproductive organs and developmental disorders affecting cognitive and behavioral functions. To minimize the risk to the fetus can be through the use of contraception and planning for pregnancy, taking valproic acid monotherapy, at a dose of less than 1000 mg/day in 2-3 divided doses, folic acid supplementation, close monitoring during pregnancy and full cooperation with doctors: a gynecologist and neurologist. The aim of this study was to measure the concentrations of valproic acid in maternal serum and cord serum and a reference to the results of the newborn. The concentrations of valproic acid in the serum was performed using high performance liquid chromatography method with fluorometric detection. Valproic acid concentration in the blood serum of patients housed or slightly exceed the therapeutic concentration. In all samples of umbilical cord blood serum were detected, no drug found to have birth defects. Born children should remain under control in order to detect possible birth defects that cannot be detected immediately after birth.