This study was planned to investigate the effect of kangaroo care and lullaby on mother-baby physiologic parameters and mother's state anxiety level in premature newborns.

Due to health problems, premature infants are subjected to many painful and uncomfortable interventions such as intubation and respiratory support, umbilical catheter, intravenous interventions, nasogastric catheter, sometimes gastrostomy, peritoneal dialysis, eye examinations and operations. The premature newborn may therefore be deprived of compassionate care that will provide comfort, such as sucking, cuddling, touching and eye contact, which are basic needs. The mother-infant relationship may be negatively affected because premature babies are different from what is imagined and have some health problems and are transferred to the intensive care unit. The birth of a premature baby, which is a crisis for the whole family, can cause intense anxiety and fear that the mother will lose her baby. The mother may avoid touching her baby for fear of harming her baby, and participating in the care of her baby can be very difficult and anxiety-provoking. Nurses working in the neonatal service and neonatal intensive care unit play a major role in ensuring mother-infant interaction in premature babies. It should enable the mother to share the same room (rooming-in), skin-to-skin contact (kangaroo care), eye-to-eye contact, hugging her baby, participating in the care of her baby and maintaining breastfeeding, which will increase the intimacy between mother and baby. Kangaroo care is a method in which newborns are placed on their mothers' chests, facing the mother, and skin-to-skin contact between mother and baby is ensured in order to ensure the early discharge of the baby from the hospital and to ensure that the baby starts to benefit from breast milk as soon as possible. Kangaroo care should be initiated as early as possible in the delivery room or neonatal intensive care unit to ensure thermal regulation, physiological stability, appropriate stimulation and to increase the rate of attachment and breastfeeding. It is known that the fetus recognizes the mother's voice from the 32nd week of gestation and in the postnatal period and responds with parameters such as increased pulse rate. It is argued that lullaby recital in neonatal intensive care has a relaxing effect on the newborn by masking environmental stressors and negative sounds. During kangaroo care, the baby's ear rests directly against the mother's breast, skin-to-skin contact and sounds are transferred to the baby through tissue and air, and the mother's voice is compared to the fetal auditory environment that the baby hears in the uterus, and it is thought that the positive effects on the mother and baby should be examined. This study was planned to examine the effect of kangaroo care and lullaby on the physiologic parameters of the mother and infant and the mother's state anxiety level in premature newborns. Thus, it is aimed to provide physiological stability in the infant and to increase mother-infant bonding by determining the effect of kangaroo care and lullaby, which are safe, inexpensive and easily applicable methods, on the vital signs of the mother and infant and the anxiety level of the mother.

Inclusion Criteria:

• The gestational age of the newborn is between 28-37 weeks,
• Stable health status of the newborn,
• Mothers' willingness to participate in the study.

Exclusion Criteria:

• The gestational week of the newborn is below 28 weeks and above 37 weeks
• Unstable health status of the newborn,
• Hospitalization for at least 3 days,
• Parents were not willing to participate in the study.

Exclusion Criteria (during the research):

• Sudden need for resuscitation
• Sudden deterioration of the stabilization of health status

Individual participant data (IPD) will be shared upon reasonable request from qualified researchers. Requests will be evaluated by the study investigators, and data will be shared in compliance with ethical and institutional regulations.