Is it safe to use lamotrigine during pregnancy? A prospective comparative observational study

Background Lamotrigine is a second‐generation antiepileptic drug, also used as a mood stabilizer. Published data on its use in human pregnancy are largely derived from pregnancy registries. Pregnancy experience in most studies has been reassuring. However, data from the North American Antiepileptic Drug Pregnancy Registry suggested an increased risk for oral clefts. The primary objective of the study was to evaluate the rate of major anomalies after lamotrigine exposure during pregnancy compared with pregnancies of women counseled for nonteratogenic exposure (NTE). Methods Callers who contacted the Israeli Teratology Information Service regarding lamotrigine treatment or NTE during pregnancy between 1997 and 2008 were prospectively followed‐up. Results The rate of major congenital anomalies was similar between 218 lamotrigine exposed pregnancies (208 in the first trimester) and 865 NTE‐pregnancies. There was no case of oral cleft in the lamotrigine‐exposed group. The median lamotrigine dose in the beginning of pregnancy was 200 mg/d. The dose was increased during pregnancy in 29%. The majority of women in the cohort (82%) were treated for neurologic indications, while 18% for psychiatric disorders. Monotherapy was taken by 72%. Conclusion The data available, thus far, on lamotrigine monotherpy‐exposed pregnancies are encouraging. However, further studies are needed to determine with greater certainty the overall risk for major anomalies, as well as the specific risk for oral clefts. Based on the current and previously published data, lamotrigine, seems a reasonable alternative for pregnant women when clinically indicated. Birth Defects Research 109:1196–1203, 2017. © 2017 Wiley Periodicals, Inc.