LAUSR

REMERA (REgistre des Malformations En Rhône‐Alpes) is a registry of congenital malformations that covers 58,000 births annually in Central‐East France. In 2010, the registry raised an alarm to the health authorities (Santé publique France, SpF) about three cases of a unilateral isolated transverse upper limb reduction defect (UITULRD) in a small subarea; the general prevalence of this defect is one case in 10,000 births. In the following years, more infants were born with the same malformation in the same territory of the Ain department. Public health authorities, supported by an expert committee, rejected the existence of a cluster, but we aim here at providing evidence for this cluster.