Executive summary
- Jaundice in the first 24 hours is pathological until proven otherwise. It needs urgent serum bilirubin measurement and urgent medical review.
- For babies more than 24 hours old, suspected or obvious jaundice still requires prompt bilirubin measurement, interpreted against postnatal age in hours.
- Primary care danger points: early jaundice, signs of acute illness, pale stools, dark urine, or prolonged jaundice.
Recognition and urgent action
- Visible jaundice in the first 24 hours: measure serum bilirubin within 2 hours and arrange urgent review within 6 hours.
- More than 24 hours old: measure bilirubin within 6 hours if jaundice is suspected or reported.
- Testing method: use serum bilirubin in babies in the first 24 hours of life or below 35 weeks' gestation. In term/near-term babies more than 24 hours old, transcutaneous bilirubin can be used first, but confirm with serum if high or near treatment thresholds.
Prolonged jaundice and community red flags
- Prolonged jaundice means beyond 14 days in a term baby or beyond 21 days in a preterm baby.
- Always ask about stool and urine colour: pale chalky stools or dark urine staining the nappy raise concern for conjugated hyperbilirubinaemia/biliary obstruction and need urgent specialist assessment.
- Work-up for prolonged jaundice includes conjugated bilirubin and other investigations according to NICE/local neonatal pathways.
- Do not use an icterometer and do not eyeball severity alone.
Frequently asked questions
What is the biggest “can’t miss” rule?
Any obvious jaundice in the first 24 hours of life requires urgent serum bilirubin measurement and urgent medical review.
When is prolonged jaundice defined?
Beyond 14 days in term babies and beyond 21 days in preterm babies.
When can I use transcutaneous bilirubinometry?
In term or near-term babies older than 24 hours. Serum bilirubin is still required in the first 24 hours, in babies under 35 weeks, and when transcutaneous readings are high or near treatment thresholds.
Transparency
This page is an educational, clinician-written summary of publicly available NICE guidance intended for trained healthcare professionals. It uses original wording (not copied text) and should be used alongside the full NICE source, local pathways, and clinical judgement. Doses provided are for general reference; always check the BNF/SPC.