[Evolution of epilepsy in successive pregnancies]

Hormonal and metabolic factors related to pregnancy itself are considered to increase the likelihood of seizure recurrence. If so, we should expect a similar evolution of epilepsy in a subsequent pregnancy. We investigated differences in evolution of non-gestational epilepsy in each pregnancy of women suffering from epilepsy.

A prospective study was conducted in order to compare seizure frequency in two successive pregnancies of more than 36 weeks duration in 12 patients. Improvement/worsening is defined as a change of +/- 50 % in the number of seizures regarding that which occurred within the previous eleven months.

Twelve epileptic women were studied during two subsequent pregnancies. Eight of them took the same antiepileptic treatment for both pregnancies and one took no antiepileptic drug. Three worsened in the first pregnancy and two in the second. Seven patients had the same seizure frequency during both pregnancies. The total plasma antiepileptic concentrations tended to decline with the same proportion in both pregnancies if the dose remained unchanged. We observed no differences in mean hormone plasma concentrations for each quarter, within subsequent pregnancies.

Except for one case with drug-resistant epilepsy, we found that the reason for the discrepancy in the frequency of the seizure between two successive pregnancies in the same patient was a sharp or rapid change in antiepileptic drug dose or non-compliance. In well controlled epileptic women a consistent evolution of epilepsy should be expected in a subsequent pregnancy, if adequate treatment is maintained.