RÉSUMÉ
OBJECTIVES: Levetiracetam is a broad-spectrum antiepileptic drug (AED) which is currently licensed in the United States and the United Kingdom and Ireland for use as adjunctive treatment of focal-onset seizures and myoclonic seizures or generalized tonic-clonic seizures, occurring as part of generalized epilepsy syndromes. In the United Kingdom and Ireland, it is also licensed as monotherapy treatment for focal-onset seizures. Previous small studies have suggested a low risk for major congenital malformations (MCM) with levetiracetam use in pregnancy. METHODS: The UK and Ireland Epilepsy and Pregnancy Registers are prospective, observational registration and follow-up studies that were set up to determine the relative safety of all AEDs taken in pregnancy. Here we report our combined results for first-trimester exposures to levetiracetam from October 2000 to August 2011. RESULTS: Outcome data were available for 671 pregnancies. Of these, 304 had been exposed to levetiracetam in monotherapy, and 367 had been exposed to levetiracetam in combination with at least one other AED. There were 2 MCM in the monotherapy group (0.70%; 95% confidence interval [CI] 0.19%-2.51%) and 19 in the polytherapy group 5.56% (3.54%8.56%) [corrected]. The MCM rate in the polytherapy group varied by AED regimen, with lower rates when levetiracetam was given with lamotrigine (1.77%; 95% CI 0.49%-6.22%) than when given with valproate (6.90%; 95% CI 1.91%-21.96%) or carbamazepine (9.38%; 95% CI 4.37%-18.98%). CONCLUSION: This study, in a meaningful number of exposed pregnancies, confirms a low risk for MCM with levetiracetam monotherapy use in pregnancy. MCM risk is higher when levetiracetam is taken as part of a polytherapy regimen, although further work is required to determine the risks of particular combinations. With respect to MCM, levetiracetam taken in monotherapy can be considered a safer alternative to valproate for women with epilepsy of childbearing age.