We assessed the utilization of antiepileptic drugs (AEDs), 1999-2005, in 4,798 prospective epilepsy pregnancies from 38 countries participating in EURAP, an international AED and pregnancy registry. Prominent differences in utilization patterns were observed across the various countries. Exposure to second-generation AEDs ranged from 3.5% in India and 7.3% in Italy to 75% in Denmark. Even wider variation was recorded in exposure to individual AEDs. The utilization of second-generation AEDs increased over time (for lamotrigine, from 9.9% of all pregnancies before 2001 to 29.6% after 2003). The differences in use of individual AEDs across countries probably reflect lack of evidence concerning the optimal treatment of epilepsy in women of childbearing age, as well as variation in country-specific traditions, medication costs, and drug promotion. Our observations underscore the need for comparative studies to investigate the factors influencing the prescription of AEDs during pregnancy, as well as their influence on pregnancy outcome.