Preterms who enter a different environment after the intrauterine period experience an adaptation process and may need special care due to conditions such as developmental disabilities or neurological disorders. In such cases, newborns may frequently be exposed to repetitive painful interventions (like IV catherization). Pain in the postnatal period can cause physiological, behavioral and metabolic changes, and changes in the functional processing related with somatosensation and pain in the long term. In this context, inadequacy in pain control may cause neurodevelopmental and behavioral problems in infants.

For these reasons, it is essential to carefully evaluate the pain status of the newborn and to perform pharmacological and/or non-pharmacological interventions. In the intrauterine 20th week, the ability to hear begins to form, and in the 26-28th weeks the level to respond to sounds is achieved. Music therapy is a method that can be used for newborns as it reaches a level that can respond to sound stimuli within weeks. Especially in the 32nd gestational week, preterm newborns begin to develop the ability to distinguish mother's voice from other sounds with regard to rhythm and intonation. Due to this developmental feature of preterm newborns, it is recommended to use the mother's voice in neonatal intensive care units. However, studies on this subject are very limited.

The main goal of care in neonatal intensive care units is to maintain the baby's life and comfort at the highest level, to minimize pain and suffering, and to ensure that it can cope with pain. In the light of all information, it is essential to strengthen scientific evidence in order to apply non-pharmacological methods in clinics. The research was planned experimentally in order to examine the effects of listening to a lullaby on pain and physiological parameters in preterms hospitalized in neonatal intensive care units. The participants will be devided in three groups. The first group will listen to the lulliby recorded with the mothers voice, the second group will listen to the the lulliby recorded with the voice of an unfamilliar female, and the third group will not listen to a lulliby. The effects will be measured by using three physiologic parameters (oxygen saturation, heart rate, and respiratory rate) and pain responses (Neonatai Infant Pain Scala) before, during, and after a painful intervention (IV catherization).

Inclusion Criteria:

• At 32-36+6 weeks of gestation
• Stable first 24 hours after birth
• Not dependent on mechanical ventilation
• Non-intubated
• Without a congenital and/or acquired malformation of hearing
• No congenital defect • Without hyperbilirinemia
• Not taking analgesics and/or sedatives in the last 24 hours
• If no painful application has been made to the newborn in the last hour (eg, blood collection, aspiration, eye examination, etc.)
• Postnatal age of 1-7 days
• Preterms whose height and weight are above the 10% percentile according to the week of gestation

Exclusion Criteria:

• Deterioration in general condition
• Those who do not meet the criteria for inclusion in the research
• Preterms whose parents did not consent to participate in the study