Periventricular leukomalacia-related litigation in Japan: a qualitative analysis of causation under clinical uncertainty.

Introduction: Periventricular leukomalacia (PVL) is a leading cause of cerebral palsy in preterm infants. However, its multifactorial pathogenesis and uncertainty regarding the timing of brain injury make causal attribution in medical litigation inherently complex. Despite its clinical significance, little is known about how courts evaluate causation and responsibility in PVL-related cases. This study aimed to clarify the clinical and judicial characteristics of PVL-related medical litigations in Japan. Methods: Cases were identified using a nationwide legal database. A qualitative analysis of judicial decisions was performed, focusing on obstetric and neonatal management, breach of duty, causation, and informed consent. Seven litigation cases involving preterm infants were included. Results: Despite substantial heterogeneity in clinical presentation and perinatal course, cross-case analysis identified several recurring patterns in judicial reasoning regarding causation and responsibility. Disputed issues arose across multiple phases of perinatal care, including the timing of delivery, fetal monitoring, maternal transfer, postnatal care systems, and respiratory management. Although judicial decisions showed considerable variability, the recognition of causation emerged as the pivotal determinant of liability. In some cases, causation was acknowledged only partially, despite persistent clinical uncertainty regarding the timing and mechanisms of injury. In contrast, in cases involving clearly identifiable intrapartum hypoxic events, courts were more likely to affirm causation by linking clinical events in a coherent temporal sequence despite the underlying medical uncertainty. Discussion: These findings demonstrate that PVL-related litigation may involve disputes across multiple phases of perinatal care because of the multifactorial nature of PVL and the uncertainty regarding the timing and etiologies of injury. Under such conditions of clinical uncertainty, legal responsibility is assessed not only through isolated medical acts but also through broader clinical decision-making processes involving critical decisions across multiple phases of perinatal care. Moreover, the results highlight a fundamental divergence between medical reasoning based on scientific evidence and legal reasoning. The findings underscore the importance of transdisciplinary decision-making, careful documentation, and effective communication in managing medico-legal risk in perinatal practice.