Monitoring serum concentrations of antiepileptic drugs in pregnancy - to do or not to do?

Antiepileptic drugs exert extensive pharmacological variability, a high adverse effect burden and numerous pharmacokinetic interactions that might be difficult in clinical practice. Implementation of therapeutic drug monitoring (TDM) is a tool to handle such challenges and facilitate individualized treatment. Pregnancy is a period where rapid physiological and pharmacokinetic changes occur, and the outcomes may be difficult to predict. Safety aspects cover the need for safe pharmacological treatment in pregnancy as well as caution for the exposure of antiepileptic drugs to the fetus and have to be balanced in the individual patient. Evidence and experience of the usefulness of TDM of antiepileptic drugs in pregnancy will be highlighted, and the conclusion is a YES-to do it for an optimal treatment outcome and safety concerns.