To assess the regional perinatal network of Burgundy (20 obstetrical units; 18,000 births/year), discharge abstracts are collected for all mothers and all neonates. Discharge abstracts are expanded with some additional data. According to the French law, data are rendered anonymous in each hospital before their transmission to the teaching hospital for statistical analysis. The linkage of all anonymous information concerning a patient is obtained. Moreover, this specific procedure allows the linkage of data concerning each mother and her corresponding neonate. This study shows that after an expanded data quality control, the linkage between data of the mothers and their infants is obtained in 99.8% of births.