Association of Maternal Antipsychotic Prescription During Pregnancy With Standardized Test Scores of Schoolchildren in Denmark.

Importance: An increasing number of individuals fill antipsychotic prescriptions during pregnancy, and concerns have been raised about prenatal antipsychotic exposure on neurodevelopmental outcomes.

Objective: To examine whether maternal prescription fill for antipsychotics during pregnancy was associated with performance in standardized tests among schoolchildren.

Design, Setting, And Participants: This register-based cohort study included 667 517 children born in Denmark from January 1, 1997, to December 31, 2009, and who were attending public primary and lower secondary school. All children had completed at least 1 language (Danish) or mathematics test as part of the Danish National School Test Program between 2010 and 2018. Data were analyzed from November 1, 2021, to March 31, 2022.

Exposures: Antipsychotic prescriptions filled by pregnant individuals were obtained from the Danish National Prescription Register.

Main Outcomes And Measures: Differences in standardized test scores (range, 1-100; higher scores indicate better test results) in language and mathematics between children of mothers with and without antipsychotic prescription fills during pregnancy were estimated using linear regression models. Seven sensitivity analyses, including a sibling-controlled analysis, were performed.

Results: Of the 667 517 children included (51.2% males), 1442 (0.2%) children were born to mothers filling an antipsychotic prescription during pregnancy. The mean (SD) age of children at the time of testing spanned from 8.9 (0.4) years in grade 2 to 14.9 (0.4) years in grade 8. Maternal prescription fill for antipsychotics was not associated with performance in language (crude mean test score: 50.0 [95% CI, 49.1-50.9] for the exposed children vs 55.4 [95% CI, 55.4-55.5] for the unexposed children; adjusted difference, 0.5 [95% CI, -0.8 to 1.7]) or in mathematics (crude mean test score: 48.1 [95% CI, 47.0-49.3] for the exposed children vs 56.1 [95% CI, 56.1-56.2] for the unexposed children; adjusted difference, 0.4 [95% CI, -1.0 to 1.8]). There was no evidence that results were modified by the timing of filling prescriptions, classes (first-generation and second-generation) of antipsychotics, or the most commonly prescribed antipsychotic monotherapies, including chlorprotixene, flupentixol, olanzapine, zuclopenthixol, quetiapine, perphenazine, and methotrimeprazine. The results remained robust across sensitivity analyses, including sibling-controlled analyses, negative control exposures analyses, and probabilistic bias analyses.

Conclusions And Relevance: In this register-based cohort study, maternal prescription fill for antipsychotics during pregnancy did not appear to be associated with standardized test scores in the offspring. The findings provide further reassuring data on offspring neurodevelopmental outcomes associated with antipsychotic treatment during pregnancy.