Shared and Disorder-Specific Prenatal and Perinatal Risk Factors for Neurodevelopmental Disorders: A nationwide cohort study.

Neurodevelopmental disorders (NDDs) are common, frequently co-occur, and impose a substantial burden, yet the extent to which early-life risk factors differ across the spectrum of NDDs remains unclear. Using the EPI-MERES Register, derived from the French National Health Data System, we conducted a nationwide cohort study of all 7.46 million children born in France between 2010 and 2018, followed until September 2024. We investigated prenatal and perinatal risk factors—including gestational age, small for gestational age (SGA), neonatal hypoxia, congenital malformations, parental age, maternal alcohol and tobacco exposure, and socioeconomic disadvantage—in relation to five major NDDs: communication disorders, learning disorders, attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder (ASD), and intellectual disability (ID). Models accounted for co-occurring NDDs. Overall, 511,619 children (6.8%) were diagnosed with at least one NDD over a median follow-up of 10.3 years. Co-occurrence was frequent, especially for ID (54.5%), ASD (52.2%), and ADHD (34.9%). Male sex, prematurity, SGA, congenital malformations, and maternal alcohol or tobacco exposure were consistently associated with elevated risk across all NDDs. Congenital malformations, extreme prematurity, and neonatal hypoxia showed strongest associations with ID. Advanced parental age was linked to ASD and ID, whereas younger parental age was associated with ADHD. Maternal alcohol exposure was particularly associated with ADHD, ASD, and ID, while tobacco exposure was linked to ADHD and learning disorders. Socioeconomic disadvantage increased risk for ASD, ID, and communication disorders, but was inversely associated with ADHD and learning disorders. These findings delineate shared and disorder-specific prenatal and perinatal risk profiles and emphasize the importance of considering co-occurring diagnoses in understanding etiological pathways and informing early prevention strategies.