BackgroundNeonatal jaundice (NNJ) is common, but few root cause analyses based on national quality registries have been performed. An online registry was established to estimate the incidence of NNJ in Turkey and to facilitate a root cause analysis of NNJ and its complications.MethodsA multicenter prospective study was conducted on otherwise healthy newborns born at ≥35 weeks of gestation and hospitalized for only NNJ in 50 collaborator neonatal intensive care units across Turkey over a 1-year period. Patients were analyzed for their demographic and clinical characteristics, treatment options, and complications.ResultsOf the 5,620 patients enrolled, 361 (6.4%) had a bilirubin level ≥25 mg/dL on admission and 13 (0.23%) developed acute bilirubin encephalopathy. The leading cause of hospital admission was hemolytic jaundice, followed by dehydration related to a lack of proper feeding. Although all infants received phototherapy, 302 infants (5.4%) received intravenous immunoglobulin in addition to phototherapy and 132 (2.3%) required exchange transfusion. The infants who received exchange transfusion were more likely to experience hemolytic causes (60.6% vs. 28.1%) and a longer duration of phototherapy (58.5 ± 31.7 vs. 29.4 ± 18.8 h) compared to infants who were not transfused (p < 0.001). The incidence of short-term complications among discharged patients during follow-up was 8.5%; rehospitalization was the most frequent (58%), followed by jaundice for more than 2 weeks (39%), neurological abnormality (0.35%), and hearing loss (0.2%).ConclusionsSevere NNJ and bilirubin encephalopathy are still problems in Turkey. Means of identifying at-risk newborns before discharge during routine postnatal care, such as bilirubin monitoring, blood group analysis, and lactation consultations, would reduce the frequency of short- and long-term complications of severe NNJ.