Identifying a Drug's Safety Profile

Antiepileptic drugs in pregnancy, and duration of pregnancy, birth weight, length, and head circumference

Margulis AV, D'Onofrio B, Almqvist C, McElrath T, Oberg AS, Plana E, Rothman KJ, Hernandez-Diaz S. Poster presented at the 34th ICPE International Conference on Pharmacoepidemiology & Therapeutic Risk Management; August 25, 2018. Prague, Czech Republic. [abstract] Pharmacoepidemiol Drug Saf. 2018 Aug; 27(S2):234. 


A group of epidemiologists and statisticians from several institutions, including RTI Health Solutions, has explored the association between the use of antiepileptic drugs in pregnancy and pregnancy duration, birth weight, length, and head circumference.

We conducted a cohort study using nationwide Swedish Registry data. The study included over 5,000 women who used antiepileptic drugs in pregnancy and had a live birth in years 1996 through 2013, along with their almost 7,000 newborn infants. 

Infants exposed to carbamazepine were born slightly earlier and were slightly smaller than infants exposed to lamotrigine. In infants exposed to various doses of carbamazepine, we observed stronger effects at higher doses. Among infants exposed to valproic acid, we observed an association between higher dose and reduced head circumference.

Our research adds to a growing body of evidence showing that each antiepileptic drug has a unique pregnancy safety profile, and that lamotrigine seems to be safer than other drugs to treat epilepsy in pregnancy.