Extremely premature newborn infants (ELNs) admitted to hospital are exposed to stressful and painful stimuli, and often to maternal separation, which can affect their long-term neurological development. Child- and family-centred developmental care (CFDC) in neonatology aims to adapt the hospital environment to the needs of the child, support the continued presence of the family and help to improve their future.

Specific assessment and appropriate analgesic treatment are therefore priorities for preserving the well-being and cerebral development of this population, which is particularly vulnerable to pain. Pain relief for certain procedures necessary for the care of newborn babies, such as venipuncture (PV), remains inadequate. Venipuncture is a common procedure in the first few weeks of life for very premature newborns. Its analgesic treatment is based on non-medicinal strategies largely carried out in the nurse's own role: non-nutritive suctioning combined with the administration of a sugar solution and wrapping. In line with the SDCEF philosophy, and reinforced by the "zero separation" concept, parental involvement in the treatment of their newborn's pain becomes natural and fundamental. A number of studies have shown the benefits of parents' presence and participation through specific isolated analgesic actions. Skin- to-skin contact (PAP) is one of these and has multiple benefits for the newborn. However, in practice, when a PV is necessary for a very premature baby, its use as a pain-relieving strategy is hampered by a number of obstacles. As NN are naturally oriented towards the maternal voice, using it is a new approach to analgesia. In an innovative study carried out in a single centre, direct maternal voice contact, in addition to the usual non- pharmacological analgesic strategies, reduced the NN's pain, without completely eliminating it during heel sampling (a skin incision known to be more painful than a PV). This analgesic strategy should therefore be combined with other non-pharmacological strategies, taking advantage of all maternal skills.

• Information visit (V0 - 1 day): parents are informed by the clinical research nurse (CRN);
• Inclusion visit (V0): inclusion, collection of consent from the 2 holders of parental authority, collection of anamnestic data by the CRI;
• Visit S and visit M (V0 to ≤ 7 d): random order, installation of the NN in a room dedicated to recordings, analgesic strategies (see below), performance at each visit of a PV (necessary for care) by the IRC, collection of behavioural data by video sequences centred on the NN's face.

Analgesic strategies during the S visit: standard and recommended non-pharmacological analgesic strategies used by the CRI: administration of sugar solution, support for non-nutritive sucking with a dummy and wrapping in a nappy.

Analgesic strategies at visit M: overall non-pharmacological analgesic strategies carried out by the mother: sucking on a sugar solution, supporting non-nutritive sucking with a dummy, contact, etc.

direct voice (from 5 minutes before to 5 min after PV), wrap in a nappy and manual, and offer to grasp the finger.

Analysis of behavioural data: NFCS scores obtained from analysis of video sequences by 10 s periods (basal, per and post stimulation) by 2 blind assessors on the type of analgesia used (carer or mother).

Inclusion Criteria:

• Very premature babies born before the gestational age (GA) of 32 weeks of amenorrhoea (SA) whose corrected age (CA) does not exceed 34 SA at the time of their participation.
• NN requiring close biological monitoring by a PV.
• Hospitalised in the NN medicine and intensive care unit at Strasbourg hospital.
• Consent obtained from both holders of parental authority.
• Person covered by a social health insurance scheme.

Exclusion Criteria:

• Any known malformation affecting one or more organs.

• Cerebral lesions discovered o n cerebral ultrasound (intraventricular haemorrhage grade > 2, periventricular leukomalacia).

• Unstable clinical state as judged by the investigator and the medical team.

• Transfer to another hospital centre expected before the end of the study period.

  • Mother: Minor. Deprived of liberty by judicial or administrative decision. Under legal protection. Severe psychological pathology. Drug addiction. Difficulty understanding and/or reading the language.

French.