Seizure control in antiepileptic drug-treated pregnancy.

This brief report covers an analysis of 7 years outcome data from the Australian Register of Antiepileptic Drugs in Pregnancy. In studying the control of antiepileptic drug-treated epileptic seizures during pregnancy, it was found that pregnancy had little influence on antiepileptic drug-treated epileptic seizure disorders. Seizures during pregnancy occurred in 49.7% of 841 antiepileptic drug (AED) treated pregnancies in women with epilepsy. Epilepsies that were active in the year before pregnancy tended to increase the risk of intrapartum and postpartum seizures. The risk of seizures during pregnancy was 50-70% less if the prepregnancy year was seizure free, and decreased relatively little more with longer periods of prepregnancy seizure control. Once there had been 1 year's freedom from seizures there seemed relatively little further advantage in deferring pregnancy to avoid seizures returning while pregnant.