Late premature infants are those who were born at GA of 34 to 36 weeks. Despite the GA, the high weight and growth rates, this group of newborns is much more likely than full-term children to experience disruptions in neonatal adaptation, damage to the respiratory system, CNS, the development of infectious complications, asphyxia, hypothermia, hypoglycemia, hyperbilirubinemia. All of these lead to an increase in morbidity, mortality and disability not only in the first months of life, but also in the future, therefore late premature infants cannot be treated as/kind of “almost full-term.” This bibliographical review represents the data on the features of the development of various pathological processes, outcomes and treatment options in late preterm infants.

The growth rate of infants born preterm should match the growth rate of healthy fetuses of the same gestational age. However, despite many existing clinical guidelines and dietary protocols, preterm infants almost invariably experience postnatal growth restriction. To ensure optimal growth and development of preterm infants, it has become essential to revise nutritional strategies. For preterm infants with extremely low and very low birth weight, it is recommended to initiate parenteral nutrition within the first hours of life, as well as to initiate early enteral nutrition directly in the delivery room with mother’s colostrum using buccal and cotton swabs. If possible, to increase the volume of enteral nutrition, to enrich breast milk, preferably with liquid fortifiers and/or human milk-based fortifiers, and to optimize supplementation with additional minerals. This review presents the scientific rationale for nutrient requirements, practical recommendations and strategies for parenteral and enteral nutrition in preterm infants, current recommendations for initial and maximum macro- and micronutrient gestational requirements. Key words: parenteral nutrition, enteral nutrition, preterm infant, nutrients, micronutrients, breast milk fortifiers

Premature infants born before 32 weeks of gestation with very low and extremely low birth weights are at higher risk for several neurodevelopmental disorders, including cerebral palsy and sensory, cognitive, and behavioral problems. The more complications are observed in the neonatal period, the higher is the likelihood of long-term complications of prematurity. Studying the factors that influence the outcome of neurological development is the only way to develop better treatment approaches.Purpose. Assessment of correlations between the brain ultrasonography data in children with very low and extremely low birth weights at birth with perinatal and neonatal risk factors, to predict neurodevelopmental outcomes and neuropsychic disorders at 2 years of corrected age.Material and methods. The material of the study was premature babies with very low and extremely low birth weights (≤32 weeks, ≤1500 g) who were born and received treatment and care in two large perinatal centers in Yerevan. Neurodevelopmental outcome in children was assessed using the Bayley-III developmental scale at 2 years of age.Results. 64% of ex-premature babies had completely normal development. 10% had cerebral palsy, 21% of children had a speech delay, 5% developed mental deficiency. Socio-emotional and behavioral problems were more common, especially in the social and practical areas (27% and 25%, respectively). 85.7% of children with motor disorders and 60% of children with speech delay had concomitant behavioral disorders. Deviations in behavior were found in 34.4% of children with normal (mental, motor, speech) development. More than 9% of children had very good results, 2% had a high level of mental development, and 3% — a high level of motor development.Conclusion. Predictors for the development of motor disorders and cerebral palsy were Grade 2 and 3 intraventricular hemorrhages, cystic periventricular leukomalacia, ventriculomegaly. Ventriculomegaly at term equivalent age, expansion of the extracerebral space and interhemispheric fissure led to combination of cerebral palsy and delayed speech development.

The morbidity and mortality of premature newborns, as well as their subsequent physical and psychomotor development were analyzed in many studies. Significantly fewer studies focused on neurosonographic examination of healthy full-term babies and their neurological characteristics later in life. Objective. To assess the effectiveness of screening neurosonography performed immediately after birth in healthy, full-term newborns by subsequent evaluation of their neurological and psychomotor development at the age of two years. Patients and methods. This study included 121 healthy full-term newborns (body weight at birth ≥ 2500 g; gestational age 39–41 weeks) born in 2018 in Yerevan, Republic of Armenia. All study participants underwent neurosonography; their neurological development at the age of 2 years was evaluated by a pediatrician using the Bayley scale. Results. No cases of serious brain lesions and hemorrhages were registered in out cohort of healthy full-term newborns. The majority of them (79%) had normal neurosonography results. The most common findings included lenticulostriate vasculopathy (7.4%), hyperechogenicity in the trigone region (6.6%), subependymal pseudocysts (1.6%), vascular plexus cysts (3.0%), and asymmetry of the lateral ventricles (3.3%). Conclusion. By the age of 2 years, problems with motor development were detected in 2% of participants, intellectual disability in 2% of participants, and speech disorders in 11% participants. None of the children had severe disability. Key words: preterm newborns, brain lesions, neurosonography, neurological development