Fetal Alcohol Syndrome (FAS), resulting from maternal alcohol consumption during pregnancy, is characterized by: dysmorphic features, growth retardation, and neurodevelopmental disorders. The objective of this study is to analyze geographic variations in FAS using the national database of the Medical Information Systems Program (PMSI). Methods: Hospitalizations occurring between 2006 and 2011 among children (age < 1 year) with a primary or associated diagnosis of FAS (ICD-10 code P043) were analyzed. Results: The prevalence of FAS in the PMSI is 0.9 cases per 10,000 births, with a significantly higher rate (>2 cases per 10,000 births) in Réunion, Upper Normandy, Nord-Pas-de-Calais, Auvergne, and Alsace. Lower prevalences are observed in regions such as Brittany, where alcohol is a public health problem (high rates of hospitalization for alcohol-related illness and regular alcohol consumption). Conclusion: The difficulty in diagnosing FAS may lead to underdiagnosis and inconsistent coding across centers. Further studies are needed to analyze the observed differences in prevalence and their causes. (R.A.)