Summary. Every year the number of preterm infants in the world and in Ukraine gradually increases - every 10th baby is born prematurely, and premature birth remains the leading cause of 50% neonatal morbidity and mortality. The general condition of this category of infants requires special knowledge and skills, psychological support, patience for both medical staff and parents, and certainly enormous material costs. This is due to the features of the neonatal period of such infants, namely the duration of respiratory support and the need for oxygen therapy, the provision of trophic and complete enteral nutrition, unstable tolerance, and the need for long-term inpatient treatment. However, all these efforts and resources don’t guarantee that the further development of premature babies will be physiological. Placental status provides an important information about explanatory factors that contributed to preterm birth, however, placental features haven’t been properly studied and the correlation between placental changes and neonatal outcomes remains poorly understood. According to the world literature, infection is one of the most important risk factors for premature birth, but the accumulation of evidence based on pathomorphological examination of the placenta and its membranes indicates that the role of specific bacterial and viral infections is not completely convincing and, as a consequence, can be less common cause of premature birth than previously suspected. Different auxiliary activities for preventing premature birth and improving the prognosis for the life and health of premature babies in later childhood’s periods are very important. A better understanding of the underlying mechanisms that regulate uterine-placental blood flow and the impact of other factors on the placenta status can improve diagnostic approaches in early pregnancy and further optimize the principles of preventive activities for both mother and baby.Aim. To establish a connection between pathomorphological changes in the placenta and the effects of premature birth.Materials and methods. A pathomorphological study of the placenta of mothers of 220 premature infants weighing less than 1500 g was performed and based on its results, 5 groups were formed according to the classification of the placental changes. The research was carried out on the basis of the Municipal non-commercial enterprise “Vinnitsa Regional Pathological bureau of Vinnitsa Regional Council” in accordance with the protocol of pathological examination of placenta (form № 013‒1 / o). The investigation was conducted with the support of the director of MNE VRPB Vinnytsia Regional Council Kholod L.P. and the head of the main department of general pathology with histological examinations Hormash P.P. The following research methods were used: macroscopy, slice staining, electronic microscopy and immunohistochemistry, etc. The health of these 220 children in the neonatal period was assessed at the stage of treatment in the Department of Anesthesiology and Neonatal Intensive Care (DANIC), and later - in the Department of Premature Newborns (DPN) of Vinnytsia Regional Children's Clinical Hospital in 2012-2018. Such clinical parameters were analyzed as gestational age, body weight, severity at birth on the Apgar scale for 1 minute, duration of respiratory support and length of hospital stay. Also the frequency of pathological conditions that caused the severity of the neonatal period was taken into account.Results. The study found that pathological changes in the placenta increase the risk of premature birth, the need for respiratory support and oxygen therapy, as well as increase the duration of inpatient treatment. The analysis of clinical indicators of 220 premature infants and pathomorphological studies of the placentas of their mothers showed that the most severe course of the neonatal period was observed in children with inflammatory changes and signs of placental immaturity. Newborns of these groups were diagnosed with a significantly higher frequency of generalized intrauterine infections and neonatal sepsis, severe CNS damage with the development of intraventricular hemorrhage and leukomalacia. The course of the neonatal period in groups of children with signs of premature placental aging and circulatory disorders was characterized by a low incidence of infections, but periventricular leukomalacia, which is an equivalent of adverse effects of preterm birth, was confirmed 5 times more often over the comparison group.Conclusions. All children included in the study had a combination of pathologies that caused the severity of the condition in the neonatal period. The condition of the placenta significantly affected the course of the neonatal period and its inherent pathologies. Thus, newborns with signs of inflammatory changes and immaturity were 10 times more likely to suffer from generalized intrauterine infections and neonatal sepsis. There were more frequent cases of intraventricular hemorrhages, leukomalacia and bronchopulmonary dysplasia in these groups of children.