Most seizures during pregnancy occur in women who already have epilepsy. During pregnancy most women will continue their previous level of seizure control, although 15-30% may experience an increase in seizures. Pregnancy-induced changes in antiepileptic drug pharmacokinetics are a major factor affecting changes in seizure control during pregnancy, although compliance is also a significant factor. Status epilepticus occurs in only 1-2% of pregnancies, and if treated appropriately and aggressively carries a fairly low risk of morbidity and mortality. Structural and metabolic changes may precipitate new-onset seizures during pregnancy. The structural causes include intracranial hemorrhage of multiple types, cerebral venous sinus thrombosis, and ischemic stroke. Metabolic causes include hyperemesis gravidarum; acute hepatitis (due to fatty liver of pregnancy or viral hepatitis); metabolic diseases, such as acute intermittent porphyria; infections, such as malaria; and eclampsia.