Abstract-- Objective: To analyze seizure control and treatment in pregnant women with epilepsy. Methods: Seizure control and treatment were recorded prospectively in 1,956 pregnancies of 1,882 women with epilepsy participating in EURAP, an international antiepileptic drugs (AEDs) and pregnancy registry. Results: Of all cases, 58.3% were seizure-free throughout pregnancy. Occurrence of any seizures was associated with localization-related epilepsy (OR: 2.5; 1.7 to 3.9) and polytherapy (OR: 9.0; 5.6 to 14.8) and for tonic-clonic seizures, with oxcarbazepine monotherapy (OR: 5.4; 1.6 to 17.1). Using first trimester as reference, seizure control remained unchanged throughout pregnancy in 63.6%, 92.7% of whom were seizure-free during the entire pregnancy. For those with a change in seizure frequency, 17.3% had an increase and 15.9% a decrease. Seizures occurred during delivery in 60 pregnancies (3.5%), more commonly in women with seizures during pregnancy (OR: 4.8; 2.3 to 10.0). There were 36 cases of status epilepticus (12 convulsive), which resulted in stillbirth in one case but no cases of miscarriage or maternal mortality. AED treatment remained unchanged in 62.7% of the pregnancies. The number or dosage of AEDs were more often increased in pregnancies with seizures (OR: 3.6; 2.8 to 4.7) and with monotherapy with lamotrigine (OR: 3.8; 2.1 to 6.9) or oxcarbazepine (OR: 3.7; 1.1 to 12.9). Conclusions: The majority of patients with epilepsy maintain seizure control during pregnancy. The apparently higher risk of seizures among women treated with oxcarbazepine and the more frequent increases in drug load in the oxcarbazepine and lamotrigine cohorts prompts further studies on relationships with pharmacokinetic changes. Risks associated with status epilepticus appear to be lower than previously reported.