The first 1-year follow-up phase took place between April 2012 and April 2013.

Of the 4,467 children released from neonatal care, 4% of families refused to participate in the follow-up set up in the Epipage 2 study. 4,190 children were included in the 1-year follow-up.
Questionnaires were sent to families to collect data on the child’s health, use of care, living conditions and the mother’s health. Questionnaires were completed for 89.5% of children contacted (3,841 children).