Pregnancy outcomes in women with surgically treated epilepsy.

OBJECTIVE: To ascertain whether epileptic seizure control during pregnancy differed between Australian women with previously surgically treated epilepsy, and those with only medically treated epilepsy. MATERIALS/METHODS: Analysis of data for 74 pregnancies of women with surgically treated focal epilepsy, compared with that from 1013 pregnancies in women with medically treated focal epilepsy, both groups drawn from the Australian Register of Antiepileptic Drugs in Pregnancy between 1999 and 2020. RESULTS: Seizures of all types, and also convulsive seizures, were less well controlled during pregnancy in the previously surgically treated cases, the difference for seizures of all types (68.9% versus 50.1%) being statistically significant (p < .05). This result was contrary to the outcome of a previously published study of the same question carried out in India. CONCLUSIONS: At present, it may be premature to conclude that previous epilepsy surgery will be associated with a better chance of seizure-free, or seizure-controlled, pregnancy.

Should valproate be taken during pregnancy?

The Australian Registry of Antiepileptic Drug Use in Pregnancy includes 172 instances in which women took sodium valproate, with or without other antiepileptic drugs, during pregnancy. These pregnancies resulted in a substantially higher (p < 0.05) rate of malformed offspring (15.1%) compared with 348 pregnant women who took antiepileptic drugs other than valproate (2.3%) and 40 pregnancies in epileptic women who took no antiepileptic drugs (2.5%). At valproate doses of 1400 mg and below per day, the mean rate of pregnancies with fetal malformations was 6.42% and did not seem to be dose-dependent. At higher valproate doses, the mean rate of pregnancy with fetal malformation was 33.9% and appeared to increase with increasing drug dosage. This finding suggests the need for reappraisal of the use of valproate in women who may become pregnant or are pregnant whilst the drug is taken. The therapeutic policy adopted may depend on whether valproate doses below 1400 mg per day are regarded as safe for the fetus. This study indicates that the risk of malformation associated with such doses was just statistically significantly (p < 0.05) higher than that associated with other antiepileptic drugs. Various possible clinical scenarios are discussed.