Pregnancy complicated by neurological disorders is a challenging area for both obstetricians and neurologists. Treatment of the maternal condition often needs to be adjusted because of concerns for the fetus, and some conditions have a major impact on the method, mode, and timing of delivery. Many of the clinical problems that arise in pregnant womb are very crucial to treat and almost all the evidence for changes in pharmacokinetics of the various antiepileptic drugs throughout gestation is derived from sequential drug monitoring and if doses are adjusted to maintain serum levels, it is possible to determine apparent clearance (daily dose/steady-state plasma concentration mL/min).