Previously, the investigators showed that preterm newborns are exposed chronically to very low radiofrequency levels in average while hospitalized in NICUs. Most of the infants were nevertheless frequently exposed to transient values above 1 V/m. The investigators also showed that an increase in RF exposure is likely to alter the activity of some neurophysiological functions and their regulatory systems in preterm newborns. The investigators hypothesize that above results are extremely specific to the location of the previous study and may be different in other NICU environments.

This study will aim at quantifying RF levels to which preterm newborns are exposed during their stay in several NICUs spread across the French territory, and assessing its impact on the central and peripheral nervous systems. The first step of this study will be to quantify the precise, continuous and individual levels of daily RF exposure to which each recruited neonate is subjected during his stay in the different NICUs from birth to 1 week postnatal life. Infants' clinical data (medical history, nutrition, morphology...) will also be continually monitored. At 1 week postnatal life, the investigators will investigate cerebral activity (EEG) and autonomic nervous system activity (ECG, heart rate variability). The impact of RF will be evaluated by analyses of the relationship between exposure levels and the various parameters extracted from the neurophysiological investigation phase.

Inclusion Criteria:

• preterm newborns born between 26-34 weeks of gestational age

Exclusion Criteria:

• infants infected,
• suffering from neurological disorders,
• serious heart, respiratory, digestive or metabolic diseases;
• infants born from mothers aged less than 18 years old or deprived of their parental rights