The purpose of this study is to evaluate the benefits of an exposition to a maternal voice and heartbeat recording during hospital stay for preterm newborns. For that, we use of a specific neonatal device "Calinange" able to record maternal voice and heartbeats and to restore it with a sound level control. We hypothesize an improvement of the well being of the newborn under Calinange exposition.

Immediately after birth, preterm newborns are immersed in a hostile environment of intensive care unit with light, sound and painful stimulations. Previously, exposure to maternal voice has demonstrated improvement on infants' statements: reduction of bradycardia, desaturation events, improvement of tolerance feeding and sleep. Unfortunatly in most of the N ICU in France, the mothers' presence attendance time is reduced because of the absence of accommodation structure. The use of a specific neonatal device able to daily record maternal voice and hearbeats and to restore it when mother is gone could improve the environment and promote the well-being of the newborn.

Inclusion Criteria:

• hospitalised premature newborn in Port-Royal NICU
• age between 3 and 6 daysof life
• gestational age between 27+0 and 31+6 weeks
• hospitalisation in one bed room
• parental consents
• beneficiaries social security scheme

Exclusion Criteria

• occurrence of one or more non-inclusion criteria
• Non-inclusion Criteria:
• Chromosomal abnormality, severe congenital malformation
• Toxic substance consumption during pregnancy
• Sedative medication in progress, High frequencies ventilation in progress
• Neurological damage: intraventricular haemorrhage stage 3 and 4, bilateral and expanse periventricular leukomalacia lesions
• Severe infectious state requiring haemodynamic support (inotropic drugs or hemissucinate)
• Participation to a other intervention research