Neonatal jaundice after discharge from the maternity unit and prolonged jaundice (more than 14 days)

• Jaundice visible or suspected before the 24th hour of life: refer urgently to the maternity unit or paediatric emergency department (serum bilirubin within 2 hours, medical opinion within 6 hours).

Laboratory tests the same day (result to be related to age in hours)

• Total and conjugated bilirubin (if transcutaneous bilirubinometry is not available, or if it exceeds 250 µmol/L)
• FBC with blood film and reticulocyte count (if intense jaundice, pallor or suspected haemolysis)if needednon-French guidelineNICE says to discuss FBC and blood film in the search for a cause in significant hyperbilirubinaemia ^[2].
• Child's blood groupif neededIn significant hyperbilirubinaemia, NICE asks for the mother's and the baby's blood group and a direct antiglobulin test (Coombs), to be interpreted according to the strength of the reaction and any anti-D injection given to the mother during pregnancy ^[2]. A family history of haemolytic disease (fetomaternal incompatibility) is a risk factor for severe jaundice ^[3].
• Direct Coombs testif neededIn significant hyperbilirubinaemia, NICE asks for the mother's and the baby's blood group and a direct antiglobulin test (Coombs), to be interpreted according to the strength of the reaction and any anti-D injection given to the mother during pregnancy ^[2]. A family history of haemolytic disease (fetomaternal incompatibility) is a risk factor for severe jaundice ^[3].
• G6PD assay (depending on family origin: Africa, Mediterranean basin, Asia; or family history)if neededNICE says to discuss G6PD measurement, taking ethnic origin into account ^[2]; G6PD deficiency in the family and parents from Asia, Africa or the West Indies are risk factors for severe hyperbilirubinaemia ^[3].

Laboratory tests

• Total and conjugated bilirubin
• FBC
• Child's blood group (and the mother's if not known)
• Direct Coombs test
• Urine microscopy and culture (if urinary tract infection suspected)if needednon-French guidelineNICE says to consider urine culture in prolonged jaundice if urinary tract infection is clinically suspected ^[2].
• Check in the health record that newborn screening (including congenital hypothyroidism) has been done.
• TSHif needednon-French guidelineThe Australian guide from the Royal Children's Hospital Melbourne (2026) measures thyroid function in every infant whose jaundice lasts more than 2 weeks, to look for primary or central hypothyroidism ^[5]. Neonatal screening, based on TSH, can miss central hypothyroidism (see the note). The words “suspected central hypothyroidism”, copied onto the prescription, justify measuring TSH and free T4 together from the outset (procedure 1211) ^[8].
• Free T4: suspected central hypothyroidismif needednon-French guidelineThe Australian guide from the Royal Children's Hospital Melbourne (2026) measures thyroid function in every infant whose jaundice lasts more than 2 weeks, to look for primary or central hypothyroidism ^[5]. Neonatal screening, based on TSH, can miss central hypothyroidism (see the note). The words “suspected central hypothyroidism”, copied onto the prescription, justify measuring TSH and free T4 together from the outset (procedure 1211) ^[8].
• Reticulocyte count (to look for haemolysis)if needednon-French guidelineThe Australian guide from the Royal Children's Hospital Melbourne (2026) measures reticulocytes and a blood film with the FBC in every infant whose jaundice lasts more than 2 weeks, looking for haemolysis ^[5].

• Pale, discoloured stools (compare with the colour chart in the health record) or dark urine: opinion of a paediatric or paediatric hepatology department the same day (biliary atresia).

If the tests are done in the community, the same day and without delaying the opinion

• Total and conjugated bilirubin
• ASTif needednon-French guidelineTests done in the community before the specialist opinion: the initial tests for infant cholestasis combine fractionated bilirubin with transaminases and GGT (a normal or low GGT points to certain genetic cholestases) ^[1].
• ALTif needednon-French guidelineTests done in the community before the specialist opinion: the initial tests for infant cholestasis combine fractionated bilirubin with transaminases and GGT (a normal or low GGT points to certain genetic cholestases) ^[1].
• GGTif needednon-French guidelineTests done in the community before the specialist opinion: the initial tests for infant cholestasis combine fractionated bilirubin with transaminases and GGT (a normal or low GGT points to certain genetic cholestases) ^[1].
• PT (prothrombin time)if needednon-French guidelineTests done in the community before the specialist opinion: prothrombin time (INR) assesses the severity of liver damage and vitamin K deficiency ^[1].
• Urine microscopy and cultureif needednon-French guidelineA urinary tract infection can present as neonatal cholestasis: urine culture should be done early in the work-up ^[1].