Valproic Acid-Induced Congenital Disorders, an Analysis in EudraVigilance and a Literature Review of Valproic Acid Utilization During Pregnancy.

Abstract

Purpose: Valproic acid (VPA) is known to increase the risk of congenital malformations during pregnancy. We evaluated VPA-induced congenital disorder reports in EudraVigilance (EV), before and after the most recent EU risk minimization recommendations in 2018, and conducted a literature review of studies capturing pregnancy exposure data to VPA.

Methods: EV public database of reports was searched for congenital ADRs for VPA, between Jan 2013 and Jun 2023. Descriptive analysis was performed to evaluate demographic data, year trends, outcomes, indications, and concomitant folic acid. A structured review of the literature based on explicit key words and eligibility criteria was conducted in PubMed and EU PAS Register (now HMA-EMA Catalogue for RWD sources) to capture pregnancy exposure to VPA. Data on study design, objectives, and results, particularly pregnancy exposure, were extracted.

Results: A total of 2021 reports containing 3210 VPA-induced congenital disorders were identified (2068 congenital malformations, 634 neural tube defects, 614 cardiac malformations). Most ages reported were between 0 and 1 months (n, 387) and for the male sex (n, 833). Generally, the outcome was "not recovered/not resolved," with 2.8% fatal ADRs reported. The number of reports slightly decreased through the years (lowest in 2015 [n, 154]; highest in 2013 [n, 669]). The literature review included 24 eligible studies, depicting varying levels of pregnancy exposure depending on the study aims and population, with an overall vast heterogeneity in presenting the study results.

Conclusions: The number of VPA-induced congenital disorder reports slightly decreased. Despite absolute contraindications, pregnancy exposure to VPA continues to occur. The present analysis signals that VPA use during pregnancy is still an actual issue despite constant risk mitigation measures.