ObjectiveTo evaluate the prevalence of and reasons for using extensively hydrolysed formulas (EHFs) of cow's milk proteins in the French neonatal units as well as the modality of their prescription for refeeding infants recovering from necrotising enterocolitis (NEC).MethodsA multicentre nationwide cross-sectional study using a questionnaire to address the prevalence of use and the reasons for prescribing EHF in hospitalised neonates and to examine the protocols and the actual reasons for their use for refeeding infants in recovery from NEC. The questionnaire was sent to only 1 senior neonatologist in each neonatal unit included in the study.ResultsMore than half of the French neonatal units participated in the survey. 91% of the surveyed units used EHF. Of 1969 infants hospitalised on the day the survey was run, 12% were fed on an EHF. 11% of the EHF prescriptions were due to previous NEC. The main reasons for using an EHF to feed infants post-NEC were the absence of human milk (75%) and surgical management of NEC (17%). When given, EHF was mainly prescribed for a period varying between 15 days and 3 months. None of the involved units continued using the EHF after 6 months of age. More than half of the surveyed units acknowledged hospitalising infants for the initiation of weaning EHF but only 21% of them tested these infants for cow's milk allergy.ConclusionsThe prevalence of EHF use in the French neonatal units is high. Refeeding infants post-NEC is one of the main reasons for such a high prevalence. The main incentive for using an EHF is the absence of human breast milk, either maternal or donor.