Contributor: Jared Scott, MD Educational Pearls: Bilirubin is natural breakdown product of red blood cells but can be neurotoxic if levels become too high Fetal red blood cells are fragile and break down easier, leading to higher bilirubin levels in neonates  Immature livers and increased intestinal absorption from sterile bowels also contribute to elevated levels and jaundice in all neonates Other risk factors for neonatal jaundice include: temperature instability, poor feeding, hypoxia at birth, and being of East Asian descent Neonatal bilirubin levels are referenced to time since birth using a nomogram to determine the need for light therapy (or exchange transfusion) References Mitra S, Rennie J. Neonatal jaundice: aetiology, diagnosis and treatment. Br J Hosp Med (Lond). 2017 Dec 2;78(12):699-704. doi: 10.12968/hmed.2017.78.12.699. PMID: 29240507. Woodgate P, Jardine LA. Neonatal jaundice: phototherapy. BMJ Clin Evid. 2015 May 22;2015:0319. PMID: 25998618; PMCID: PMC4440981. Colletti JE, Kothari S, Jackson DM, Kilgore KP, Barringer K. An emergency medicine approach to neonatal hyperbilirubinemia. Emerg Med Clin North Am. 2007 Nov;25(4):1117-35, vii. doi: 10.1016/j.emc.2007.07.007. Erratum in: Emerg Med Clin North Am. 2008 Feb;26(1):xi. Kothori, Samip [corrected to Kothari, Samip]. PMID: 17950138. Summarized by Jackson Roos, MS4 | Edited by Erik Verzemnieks, MD   The Emergency Medical Minute is excited to announce that we are now offering AMA PRA Category 1 credits™ via online course modules. To access these and for more information, visit our website at www.emergencymedicalminute.com/cme-courses/ and create an account.