Prenatal carbamazepine exposure impacts on academic performance, study finds

Lower scores on the Danish and mathematics portions of the 9th grade exit test were indicative of inferior academic achievement in adolescence in those who had been exposed to carbamazepine in-utero, says an population based article published in the Journal of Neurology.

A dibenzazepine derivative known as carbamazepine is approved to treat trigeminal neuralgia's paroxysmal pain as well as act as an antiepileptic and mood stabilizer. Absolute risk estimates for baby congenital malformation risk associated with carbamazepine monotherapy exposure during pregnancy range from 3.8% to 6.2% (i.e., up to a three-fold increase over background rates). In order to determine if children born to mothers who took carbamazepine during pregnancy had inferior academic performance in adolescence, Tai Ren and colleagues carried out this study.

All live-born single Danes who took the national 9th grade exit test between 1996 and 2002 were included in this population-based cohort study (n=370,859). Infants whose mothers had been prescribed antiseizure drugs other than carbamazepine during pregnancy were not included. The relationship between in utero exposure to maternal carbamazepine used during pregnancy (n=290) and child academic achievement, as measured by Danish and mathematics scores on the 9th grade exit test, was investigated. In order to account for socioeconomic characteristics and probable indications, such as epilepsy and treatment for other mental diseases, the mean z-score difference was calculated using linear regression. Confounding by indication was also examined in additional analyses that compared in utero exposure to past exposure and past exposure to never exposure. A positive control was in utero exposure to valproate monotherapy, and a negative control was in utero exposure to lamotrigine.

The key findings of this study were:

Adolescents in utero exposed to maternal carbamazepine monotherapy at 16.1 years of age performed worse on the 9th grade exit exam in both Danish and mathematics. 

While past exposure to carbamazepine was only associated with a slight decline in offspring's academic performance, in utero exposure to carbamazepine monotherapy was associated with lower scores than past exposure alone. 

In utero exposure to valproate monotherapy also showed an association, but in utero exposure to lamotrigine did not.

In conclusion, due to limitations in the current investigation and inconsistent findings in other studies, further research is required to corroborate these findings.

Reference:

Ren, T., Yi Lee, P. M., Li, F., & Li, J. (2022). Prenatal Carbamazepine Exposure and Academic Performance in Adolescents: A Population-Based Cohort Study. In Neurology (p. 10.1212/WNL.0000000000201529). Ovid Technologies (Wolters Kluwer Health). https://doi.org/10.1212/wnl.0000000000201529