OBJECTIVES: To examine the risk of malformations and fetal growth in the children of women treated with anticonvulsant drugs in North Jutland County, Denmark. MATERIAL AND METHODS: All women treated with anticonvulsant drugs in the county were identified in a Pharmaco-Epidemiological Prescription Database and linked to the Danish Medical Birth Registry and the Regional Hospital Information system. RESULTS: We identified 235 pregnancies where the mothers had used prescriptions for anticonvulsants around conception and/or during pregnancy, and 17,259 unexposed pregnancies where the mothers had not used prescriptions. One case of neural tube defect was found among 15 malformations in the exposed cohort. The overall odds ratio for malformations was 2.2 (95% confidence intervals 1.3-3.8). The odds ratios for low birth weight and preterm delivery were respectively 1.5 (95% confidence intervals 0.6-3.7) and 1.6 (95% confidence intervals 1.0-2.5). CONCLUSION: We found an increased risk of congenital malformations and a tendency to growth retardation in the children of women taking anticonvulsants.