Modern clinical guidelines in neonatology consist list of risk groups of severe form of neonatal jaundice in newborns, but there is a lack of authenticityof clinical and paraclinical criteria’s, which could have allowed to forecast the severity ofpathological course and to define the predictors and early signs of dysfunction of hepatobiliary system for timely conducting of medical correction in neonatal period.
 Objective.To conduct the analysis of risk factors of somatic pathology, course of pregnancy andchildbirthof pregnant, clinical and paraclinical peculiarities of early neonatal adaptation of kids considering gestational age in time of birth for defining of risk groups of newborns with severe form ofhyperbilirubinemia.
 Materials and methods.Researched peculiarities of somatic anamnesis, gestational periods course and childbirth of 141 women, whose kids had clinical signs of neonatal jaundice. Main researched groups of newborns: I group includes mature newborns, whowere divided on two subgroups: subgroup IA (46 kids) – kids that had middle condition severity and subgroup IB (23 kids) – kids with severe condition. II (control) group consist of 72 healthy mature newborns. III group includes premature newborns with gestation period 34 – 37 weeks. Consequently, IIIA group consist of 28 newborns with middle condition severity, IIIB group – kids with severe general condition in neonatal period. IV group includes conditionally healthy newborns with defined gestation period. Criteria of excluding from research were: premature childbirth (gestation period < 34 weeks), infectious genesis jaundice (P36), confirmed congenital organic pathology of hepatobiliary system, in particular: anomaly of development of gallbladder, atresia of bile duct (Q44), congenital viral hepatitis (P53.3)
 Result and discussions. Maternity factors that complicate the pregnancy course and had an importance for severity of pathological course in kids, who had a clinical sign of hyperbilirubinemia in perinatal pathology: age of pregnant, especially in premature childbirth, infertility and uncontrolled misbirthof anamnesis, placental dysfunction,threat of premature birth in this pregnancy by rhesus factor. According to scale “Risk Score for Neonatal Hyperbilirubinemia” (2004), was distinguished some tendency of increasing of severity risk of hyperbilirubinemia in perinatal pathology of mature newborns, but that tendency didn’t exist in premature newborns. The most frequent clinical symptoms in newborns with hyperbilirubinemia in perinatal pathology were: hepatosplenomegaly, bowels dysfunction, hypoglycemia, anemic syndrome, combined hemorrhagic disorders. Indicators of biochemical blood’s spectrum of newborns showed increased level of general bilirubinserum, mainly for non-conjugate fraction, decreased level of general protein,albumin and glucose, possible increasing of AsAT activity in middle severity of condition, that tells about its activation, decreasing of indicator in severe condition; AsAT activity of premature newborns had a tendency of increasing in both middle and severe condition of newborns. AlAT indicator had a possible increasing of activity in correlation with increasing of conditions severity of mature newborns and decreased ferment reaction – in premature newborns. Сonclusions. 1. Estimation of probability of severe hyperbilirubinemia development in newbornshas to be complex, considering risk factors of pregnant and her somatic, obstetric and gynecological anamnesis, course of pregnancy and of childbirth and with conducting of marks estimation of factors according recommendations of «Risk Score for Neonatal Hyperbilirubinemia» (2004). 2. Important role for prevention of development of severe form of hyperbilirubinemia has estimation of risks in newborns, considering nature of perinatal pathology course, timely detectionof clinical symptoms, existentin disorders of metabolism and transport of bilirubin.