The Effects of Pacifier-Activated Lullaby on Oral Feeding Among Preterm Infants

Premature infants frequently experience feeding difficulties because the coordination of sucking, swallowing, and breathing develops during the later stages of gestation. Many infants born very preterm require prolonged tube feeding before they can safely and effectively feed by mouth. Delays in the transition from tube feeding to full oral feeding may contribute to prolonged hospitalization, increased healthcare utilization, and challenges in growth and development.

Non-nutritive sucking (NNS), such as sucking on a pacifier without receiving nutrition, is considered an important developmental precursor to oral feeding. Previous studies have suggested that NNS may improve feeding readiness, support maturation of oral motor skills, and facilitate the transition to oral feeding. Researchers have also explored whether positive reinforcement techniques can further enhance these feeding behaviors.

The Pacifier-Activated Lullaby (PAL) system is an FDA-cleared device designed to reinforce non-nutritive sucking through auditory feedback. The system consists of a pressure-sensitive pacifier connected to a music player. When an infant generates a suck that meets a predefined threshold, the device plays a recorded voice, typically the infant's mother singing lullabies. The intervention is based on principles of operant conditioning, with the auditory stimulus serving as a reward for effective sucking behavior.

This study was designed to evaluate whether PAL therapy improves oral feeding performance in preterm infants compared with standard neonatal feeding care alone. The trial was conducted in the Level IV Neonatal Intensive Care Unit (NICU) at Nemours Children's Hospital in Orlando, Florida.

Eligible participants were preterm infants born at less than 32 weeks gestational age who had reached approximately 34 to 36 weeks postmenstrual age and were transitioning from tube feeding to oral feeding. Infants were required to be receiving a substantial portion of their nutrition enterally while still developing oral feeding skills. Infants requiring significant respiratory support or considered unsafe for oral feeding were excluded.

Participants were randomly assigned to either the intervention group or the control group. Infants in the intervention group received PAL therapy in addition to standard feeding care. During PAL sessions, a recording of the mother's voice or a caregiver's voice was played whenever the infant generated an adequate non-nutritive suck on the PAL pacifier. Infants in the control group received standard feeding care, including routine opportunities for non-nutritive sucking and developmental care practices used in the NICU.

Researchers evaluated multiple measures of feeding performance, including oral feeding proficiency, feeding efficiency, milk transfer, feeding duration, growth, progression toward full oral feeding, and related clinical outcomes. Safety was monitored throughout the study, and PAL sessions were discontinued if infants exhibited signs of physiologic instability or feeding intolerance.

The purpose of this study was to determine whether reinforcing non-nutritive sucking with an auditory reward could accelerate the development of feeding skills and improve clinical outcomes in preterm infants. The findings may help clinicians better understand the role of music-assisted and behavioral reinforcement interventions in neonatal feeding therapy and identify patient populations most likely to benefit from these approaches.

Inclusion criteria

• Preterm infants born at less than 32 weeks gestational age
• Postmenstrual age between 34 0/7 and 35 6/7 weeks at enrollment
• Receiving at least half of nutritional intake enterally and less than half orally
• Written informed consent obtained from parent(s) or legal guardian(s)

Exclusion criteria

• Mechanical ventilation at enrollment
• Continuous positive airway pressure (CPAP) support
• High-flow nasal cannula support >2 L/min
• Determined by the treating medical team to be unsafe for oral feeding
• Determined by feeding or speech specialists to be unsafe for oral feeding
• Clinical instability preventing participation in study procedures