Use of nervous system medications with fetal risk before and during pregnancy in an Argentine social security system

Objective: To describe the dispensing of nervous system medications before and during pregnancy, according to the fetal risk category of the drug. Material and methods: Descriptive drug utilization study of nervous system medications in a historical cohort (2020–2023) of pregnant women enrolled in a health insurance program in Argentina. Dispensed drugs were categorized into two groups: high fetal risk and non-high or unknown risk, based on the classification of selected regulatory agencies. The prevalence of use before and during pregnancy was measured, along with the cumulative incidence of drug discontinuation and initiation during pregnancy. Results: Among the 6,369 pregnant women included, 4.7% received at least one drug from the evaluated group in the pre-pregnancy period, and 18.8% during pregnancy. This increase was mainly due to paracetamol, which rose from 1.5% to 13.4% during pregnancy. In contrast, the use of anxiolytics (1.6% to 0.7%), antidepressants (0.8% to 0.4%), and antiepileptics (0.7% to 0.4%) decreased. The prevalence of use of high-risk medications declined from 1.5% to 1% during pregnancy, with a cumulative discontinuation incidence of 81.3% and initiation incidence of 0.7%. Conclusions: The dispensing of nervous system medications with high fetal risk was low in the studied cohort. Identifying the fetal risk associated with each drug is essential to optimize treatment selection for nervous system disorders in pregnant women. Prospective studies are needed to validate medication utilization patterns in the region and their associated fetal and neonatal outcomes.