Epilepsy and pregnancy. Factors associated with epileptic seizures during pregnancy

The management of epilepsy during pregnancy requires optimal seizure control, avoiding the potential teratogenic effects of antiepileptic drugs. This study aims to describe the clinical characteristics and perinatal outcomes of pregnant patients with epilepsy; to analyse the factors associated with seizures during pregnancy; to describe the most commonly used antiepileptic drugs in these patients; and to analyse changes in treatment regimens in 2 periods, 2000-2010 and 2011-2018. We conducted a prospective observational study of patients with epilepsy who reported their pregnancy between 2000 and 2018. Patients were evaluated in the first and second trimesters of pregnancy, after delivery, and at one year. Data were collected on demographic variables, epilepsy, and perinatal and obstetric variables. A total of 101 pregnancies were included. Patients' mean age was 32.6 years; 55.4% had focal epilepsy, 38.6% had generalised epilepsy, and 5.9% had undetermined epilepsy. We recorded 90 live births, 9 miscarriages, and 5 cases of congenital malformations, 4 of which were born to women who received valproate monotherapy. Forty patients (39.6%) presented seizures, with 16 (40%) presenting generalised tonic-clonic seizures. The variables associated with seizures during pregnancy were poor seizure control in the year prior to pregnancy (66.7% vs. 15.1%; P < .001), treatment with 2 or more antiepileptic drugs (30% vs. 14.8%; P < .001), and untreated epilepsy (25% vs. 0%; P < .001). The antiepileptic drugs most widely used in monotherapy were lamotrigine (n = 19; 27.1%), valproate (n = 17; 24.2%), and levetiracetam (n = 12; 17.1%). In the most recent period (2011-2018), we observed a greater proportion patients receiving monotherapy (81.5%, vs. 55.3%), as well as a decrease in the use of carbamazepine (2.3%, vs. 23.1%) and valproate (20.5%, vs. 30.8%); and a marked increase in the use of levetiracetam (27.3%, vs. 0%). The factors associated with the presence of seizures during pregnancy were previous poor seizure control, treatment with 2 or more antiepileptic drugs, and lack of treatment during pregnancy. The most commonly used drugs were lamotrigine, valproate, and levetiracetam, with an increase in levetiracetam use and a decrease in valproate use being observed in the later period (2011-2018).