This study could help identify aggravating or protective genetic polymorphisms associated with cerebral palsy. Populations of premature babies at different risk of cerebral palsy could thus be individualized with an impact on their monitoring and on the pathophysiological understanding of the processes leading to neurological lesions.

Inclusion Criteria:

• children born prematurely at term <34 weeks between 2008 and 2015
• assessed at the age of 2 within the Growing Together Network in Pays de Loire
• parental consent for the collection of data from their child and for intraoral sampling for the search for genetic factors.

Exclusion Criteria:

• children who died after the age of 2
• children who refused and / or whose parents refused to participate in the study

Children born prematurely at term <34 weeks between 2008 and 2015, and presenting with cerebral palsy at the age of 2 years within the Growing Together Network in Pays de Loire.

Matching by a propensity score to a population of control children with a comparable probability of developing cerebral palsy but whose examination at 2 years is optimal