The Effect of Oral Motor Intervention and Chronobiological Approach to Feeding Models Applied to Preterm Infants on Infants' Readiness to Feed, Transition to Total Oral Feeding, and Body Weight

Premature birth is defined as birth occurring before the 37th week of gestation, and approximately 15 million babies are born this way worldwide each year. Premature babies experience feeding difficulties because their oral feeding skills, sucking-swallowing-breathing coordination, and oral structures are not fully developed. Their oral motor systems typically mature between 32-34 weeks of gestation. The development of the oral motor system is crucial for adequate nutrition, growth, and weight gain. Several methods are used to improve the oral motor development of premature babies. Oral motor interventions involve physical stimuli applied to intraoral structures such as the lips, tongue, cheeks, gums, and palate. These methods aim to increase the functional strength of oral muscles and target neuro-behavioral synergy.

Oral motor interventions applied in NICUs have been shown to accelerate the transition to oral feeding, increase weight gain, and shorten hospital stays in premature infants. Premature Infant Oral Motor Intervention (PIOMI) is one of the interventions applied in NICUs. Studies have shown that PIOMI is more effective than other interventions in this field. Furthermore, no negative side effects of PIOMI have been reported.

Breast milk is an ideal source of nutrition for the growth and development of preterm infants. It provides essential nutrients for the baby's growth and development, as well as containing biological cues that help regulate circadian rhythms. For the fetus, which has become accustomed to the mother's circadian rhythms during intrauterine life, it supports this transition process by providing similar cues after birth. The composition of breast milk can vary depending on gestational age, lactation stage, and pumping time. Differences are particularly observed between day and night breast milk in terms of circadian rhythms. Daytime milk contains higher levels of substances such as immune system-related nucleotides, interleukins, and antioxidants, while nighttime milk is rich in sleep-regulating components such as melatonin and tryptophan. This difference is important for the transmission of the mother's biological rhythms to the baby, contributing to the regulation of the baby's sleep-wake cycle and improving its environmental adaptation.

The chronobiological feeding model suggests that expressed breast milk be given in periods of day and night, or more specifically, in six-hour cycles, in accordance with the daily cycle. This approach aims to support the development of the infant's circadian rhythm through expressed breast milk in situations where breastfeeding is not possible. A review of the literature revealed no studies that combined PIOMI with chronobiological feeding. Therefore, this research was planned to determine the effects of oral motor intervention (PIOMI) and chronobiological feeding on feeding readiness, transition to total oral feeding and body weight in preterm infants hospitalized in the NICU.