Autonomic maturation in neonatal period and early neurologic development: perspective longitudinal cohort study

Describe the profile of maturation of the autonomic cardiac system (through time and frequency analysis of the heart rate variability from polysomnographic 24 hours records) during the firsts two years of life (0, 6, 12, 18 and 24 months) in a full-term or premature infants cohort. Secondary objectives: - Correlate in this cohort the autonomic status at birth and the neurological psychomotor becoming at 2 years; - Describe autonomic evolution profile during the firsts two years of life; - According to specific pregnancy criteria; - According to morphometry data; - According to respiratory, cardiac, neurological, digestive, infectious neonatal morbidity criteria; - According to the incidence of severe diseases and rhythmic disorders during the two firsts two years of life.