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Health condition · Clinically reviewed

Infant jaundice, when it’s normal, when it’s not, and what to do next.

Most newborn jaundice is mild and settles on its own. A clear, NICE-based pathway is what keeps the rare, serious causes from being missed.

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Why trust this guide

  • 01

    Clinically reviewed

    Written by our editorial team and reviewed by a registered UK clinician before publication.

  • 02

    Sourced from guidance

    Checked against NICE CG98, RCPCH and peer-reviewed neonatal sources you can see at the end.

  • 03

    Current for 2026

    Reflects modern UK guidance on transcutaneous bilirubinometry, LED phototherapy and prolonged-jaundice pathways.

Key facts

Infant jaundice at a glance.

The essentials, in plain English - what it is, how common it is, and how it’s assessed in the UK today.

  • What it is

    Yellow discoloration of a newborn baby’s skin and eyes caused by a build-up of bilirubin - a normal breakdown product of red blood cells.

  • How common

    Very common - affects more than 60 per cent of term babies and more than 80 per cent of preterm babies in the first week of life.

  • Physiological pattern

    Appears after 24 hours, peaks at 3 to 5 days, and resolves over 1 to 2 weeks - usually mild and self-limiting.

  • Prolonged jaundice

    Beyond 14 days in a term baby or 21 days in a preterm baby - always needs review to exclude liver or metabolic causes.

  • Assessment

    Transcutaneous bilirubin (TcB) screens babies of 35 weeks and over; serum bilirubin (SBR) plotted on a NICE treatment-threshold graph guides care.

  • Why it matters

    Very high unconjugated bilirubin can cross into the brain and cause kernicterus - rare, permanent and almost entirely preventable.

Why this guide matters

Common and mostly benign - but never brushed off.

A structured NICE-based approach separates the common physiological pattern from the rare cases that need urgent specialist care.

  • Most cases are physiological

    Jaundice appearing after 24 hours, peaking at 3 to 5 days and clearing over 1 to 2 weeks is the usual pattern in a well, feeding baby.

  • Timing tells you a lot

    Jaundice under 24 hours old, or that lasts beyond 14 days in a term baby, is never assumed to be normal.

  • Split bilirubin catches biliary atresia

    A conjugated component in a prolonged-jaundice screen is the single most important test for finding biliary atresia early - when Kasai surgery works best.

How the diagnosis is made

From first yellow tinge to a clear plan.

The steps a UK midwife, GP or neonatal team will normally follow per NICE CG98 - so you know what to expect and why.

  1. 01

    Assessing

    Clinical assessment

    Onset, feeding, wet nappies, stool colour and family history - jaundice appearing in the first 24 hours is always pathological.

  2. 02

    Assessing

    Transcutaneous bilirubin (TcB)

    Non-invasive skin measurement used to screen babies of 35 weeks and over per NICE CG98.

  3. 03

    Assessing

    Serum bilirubin (SBR)

    A capillary or venous blood test when TcB is elevated, in babies under 35 weeks, or when treatment is being considered.

  4. 04

    Confirming

    Plot on threshold graph

    Bilirubin is plotted against gestation and hours of life on the NICE treatment-threshold chart to decide phototherapy or exchange transfusion.

  5. 05

    Confirming

    Cause-finding bloods

    FBC and film, blood group, direct Coombs test, G6PD, LFTs and TFTs - arranged by specialist neonatal or paediatric teams.

  6. 06

    Confirming

    Split (conjugated) bilirubin

    Any conjugated component in a prolonged jaundice screen is always abnormal and prompts urgent specialist paediatric hepatology review.

  7. 07

    Preparing

    Imaging and infection screen

    Liver ultrasound and infection screen (blood, urine and where indicated CSF) when a pathological cause is suspected - specialist commissioned.

Typical timeline: from screening to a settled plan in hours to days, not weeks.

Symptoms

What infant jaundice actually looks like.

The classic yellow tinge, the feeding pattern that goes with it, and the features that turn a routine review into an emergency.

  • Yellow skin and sclerae

    Yellow tinge starting at the face and spreading down the trunk and limbs as bilirubin rises.

  • Sleepy or reluctant to feed

    Higher bilirubin levels can make babies drowsy, which in turn worsens dehydration and jaundice.

  • Poor weight gain and dehydration

    Fewer wet nappies, dry mouth and weight loss over 10 per cent point to breastfeeding-failure jaundice.

  • Pale stools and dark urine

    A red flag for conjugated jaundice and possible biliary atresia - needs urgent specialist review.

  • Prolonged jaundice

    Jaundice persisting beyond 14 days in a term baby or 21 days in a preterm baby is never ignored.

  • Bruising or cephalohaematoma

    Extensive bruising or a scalp haematoma provides an extra load of red-cell breakdown and higher bilirubin.

  • Family or ethnic risk factors

    G6PD deficiency, hereditary spherocytosis, ABO or Rh incompatibility and East Asian, African or Mediterranean heritage raise risk.

  • Red flag - unwell newborn

    Fever, hypothermia, apnoea, high-pitched cry, arching or seizures with jaundice is a neonatal emergency.

Treatment

How infant jaundice is treated in the UK.

Feeding support first, phototherapy for elevated levels, and specialist commissioned care for haemolytic, infective and surgical causes.

  • Feeding support and hydration

    Frequent breastfeeding, lactation support, expressed breast milk or, where needed, supplemental feeds - the first step in most mild cases.

  • Low-dose LED phototherapy

    Blue-green light converts unconjugated bilirubin into water-soluble forms the baby can excrete - delivered on a specialist neonatal unit.

  • Intensive (multiple) phototherapy

    Double or triple lights used when levels are close to exchange thresholds or rising rapidly despite standard phototherapy.

  • Intravenous immunoglobulin (IVIG)

    For isoimmune haemolysis (Rh or ABO) when bilirubin keeps rising on intensive phototherapy - specialist neonatal decision.

  • Exchange transfusion

    Replaces the baby’s blood in aliquots to remove bilirubin and antibodies - reserved for very severe unconjugated jaundice at specialist centres.

  • Kasai portoenterostomy

    Urgent specialist commissioned surgery for biliary atresia, ideally within 60 days of life - see our guide to the Kasai procedure.

  • Treat the underlying cause

    Infection, hypothyroidism, galactosaemia, G6PD deficiency and hereditary spherocytosis each need their own specialist pathway.

  • MDT follow-up

    Specialist neonatal team, paediatric hepatology, metabolic and haematology input where required - always specialist commissioned.

What this guide is based on

The sources behind every claim on this page.

UK national guidance and specialist society standards, current at the time of last review.

Key references

Guidelines and standards we relied on.

A quiet reminder

This guide is for information, not medical advice.

Your midwife, health visitor, GP or neonatal team knows your baby and can tell you which parts of this apply. If in doubt, get seen the same day.

  • NICE. Jaundice in newborn babies under 28 days (CG98).

  • RCPCH. Prolonged neonatal jaundice pathway and standards.

  • British Association for Paediatric Hepatology, Gastroenterology and Nutrition (BSPGHAN). Biliary atresia guidance.

  • UK National Screening Committee. Newborn and infant physical examination (NIPE) standards.

Red flags

When infant jaundice needs urgent attention.

Most newborn jaundice is safely managed in the community. These are the situations that aren’t - and where specialist neonatal or paediatric hepatology input is needed straight away.

  • Jaundice in the first 24 hours

    Always pathological until proven otherwise - needs urgent bilirubin measurement and specialist neonatal review.

  • Rapidly rising bilirubin

    A rise of more than 8.5 micromol/L per hour, or levels close to the exchange line on the NICE chart, is a neonatal emergency.

  • Prolonged jaundice

    Beyond 14 days in a term baby or 21 days in a preterm baby - triggers a full prolonged-jaundice screen including split bilirubin.

  • Pale stools and dark urine

    A red flag for biliary atresia. Any conjugated component means urgent paediatric hepatology review - Kasai works best before 60 days.

  • Unwell baby with jaundice

    Fever, hypothermia, poor feeding, lethargy, apnoea or a bulging fontanelle points to sepsis and needs emergency admission.

  • Signs of kernicterus

    High-pitched cry, arching (opisthotonos), abnormal tone, seizures or coma - a paediatric emergency and always specialist commissioned.

  • Significant weight loss

    More than 10 per cent loss of birth weight, fewer than 6 wet nappies a day or dry mucous membranes - review the same day.

  • Known haemolytic risk

    Rh or ABO incompatibility, G6PD deficiency or hereditary spherocytosis warrants earlier and closer bilirubin monitoring.

  • Family history of liver disease

    Alagille syndrome, cystic fibrosis or metabolic disease in the family lowers the threshold for a full liver screen.

Living with it

A common condition, with a clear pathway.

Four things that make the biggest difference in the first weeks - feeding, looking, keeping the reviews and knowing when to escalate.

A quiet reminder

You are not being over-anxious for asking.

Midwives, health visitors and GPs would rather see a well baby who turns out fine than miss the one who isn’t. Ask.

  1. 01 Feeding

    Feed early and often

    Eight to twelve breastfeeds a day supports hydration and helps clear bilirubin. Ask your midwife or health visitor for feeding support if it’s not going well.

  2. 02 Watching

    Learn what to look for

    Check the whites of the eyes and gums in natural daylight, count wet nappies, and note stool colour - pale stools always warrant review.

  3. 03 Follow-up

    Keep the reviews

    Midwife, health visitor and GP checks in the first two weeks are how jaundice is caught early - especially the day-5 and day-10 to 14 visits.

  4. 04 Escalate

    Don’t wait if you’re worried

    Contact your midwife, GP or 111 the same day if your baby is more yellow, sleepy, feeding poorly or has pale stools.

Frequently asked

Everything we get asked about infant jaundice.

Quick answers on assessment, phototherapy, biliary atresia and breastfeeding.

  • What is infant jaundice?

    Infant jaundice - also called neonatal jaundice - is yellow discoloration of a newborn’s skin and eyes caused by a build-up of bilirubin from the normal breakdown of red blood cells. It affects more than 60 per cent of term and more than 80 per cent of preterm babies in the first week.

  • When is jaundice a worry rather than normal?

    Jaundice appearing in the first 24 hours, jaundice that lasts beyond 14 days in a term baby or 21 days in a preterm baby, jaundice with pale stools and dark urine, or an unwell baby with jaundice are all reasons to seek urgent review. Everything else is usually physiological and settles by 1 to 2 weeks.

  • How is the bilirubin level measured?

    Per NICE CG98, babies of 35 weeks and over are screened with a transcutaneous bilirubinometer - a non-invasive skin measurement. A serum bilirubin blood test is used when the screening result is high, in preterm babies, or when treatment is being considered.

  • What is phototherapy and is it safe?

    Phototherapy uses blue-green LED light to convert unconjugated bilirubin into forms the baby can excrete. It is safe, well-established and delivered on a specialist neonatal unit. Babies wear eye protection, feeding continues and most only need it for a day or two.

  • What is biliary atresia and why is it urgent?

    Biliary atresia is a rare progressive disease that blocks the bile ducts of the newborn liver. It causes conjugated jaundice with pale stools. The Kasai portoenterostomy - a specialist commissioned neonatal operation - works best when done before 60 days of life, so any conjugated component in a prolonged-jaundice screen prompts urgent paediatric hepatology review.

  • Should I stop breastfeeding if my baby has jaundice?

    Almost never. Breast-milk jaundice is common, late-onset and can last 1 to 3 months without any harm. Breastfeeding-failure jaundice - from underfeeding and dehydration - is treated by supporting feeding, not stopping it. Any decision to interrupt breastfeeding is a specialist one and rarely needed.

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