Antipsychotic Prescriptions for Prenatal and Postpartum Women in Japan: A Large Claims Database Study

This study aimed to evaluate the prevalence of antipsychotic prescriptions before, during, and after pregnancy in Japan, with a focus on new prescriptions and continuation after pregnancy confirmation. We conducted a claims-based analysis using a Japanese claims database (analytic period: 2010-2022). Antipsychotic prescription prevalence and new prescriptions were assessed from 180 days before pregnancy through 180 days postpartum. To assess continuation after pregnancy confirmation, prescription status was evaluated across gestational weeks 0-4, 5-13, and from 14 weeks to delivery. Among 120 735 women, 1698 (140.6/10 000 deliveries) received at least one antipsychotic prescription, including 809 (67.0/10 000 deliveries) during pregnancy. Prescription prevalence decreased during the first and second trimesters but increased postpartum. New prescriptions were less frequent during pregnancy but increased after delivery. Among 611 women prescribed antipsychotics during 0-4 weeks' gestation, 482 (78.9%) continued and 129 (21.1%) discontinued prescription during weeks 5-13; of those who continued prescription during 5-13 weeks, 334 (54.7%) continued until delivery. Evaluation of major indications showed that continuation until delivery was highest in those with schizophrenia (63.6%), followed by bipolar disorder (51.0%). This study provides the first comprehensive description of perinatal antipsychotic prescription trends in Japan. Substantial prescription discontinuation occurred after pregnancy confirmation. Increases in postpartum prescriptions might reflect new prescriptions or resumption among women who had discontinued treatment during pregnancy. These findings offer foundational epidemiological insights into real-world perinatal antipsychotic use.