Abstract
Differences of sex development (DSD) are congenital conditions in which chromosomal, gonadal, and anatomical sex characteristics are discordant with typical male or female development. These clinical practice guidelines provide evidence-based recommendations for the diagnosis and management of individuals with DSD across the lifespan. The guidelines were developed by a multidisciplinary committee of specialists representing pediatric endocrinology, adult endocrinology, urology, gynecology, psychiatry, and psychology. The committee employed a systematic review of the literature and used the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system to assess the strength of recommendations and the quality of evidence. Key areas addressed include the initial management of infants with atypical genitalia, diagnostic approaches, hormonal treatment, surgical interventions, gonadal tumor risk assessment, fertility preservation, and the transition from pediatric to adult care. The guidelines integrate international best practices with Japan's unique sociocultural, healthcare, and legal contexts for optimal DSD management and aim to improve clinical care for individuals with DSD while acknowledging the limited high-quality evidence in many aspects of DSD management.