Baby jaundice is a yellow tint of the skin and the whites of the eyes caused by a buildup of bilirubin; it is usually mild, shows up in the first days of life and most often fades within 2 weeks.
Newborn jaundice is very common: the American Academy of Pediatrics (AAP) notes that more than 80% of newborn infants will have some degree of jaundice, and Mayo Clinic says most need no treatment.
Every baby is watched because, rarely, bilirubin climbs high enough to harm the brain, an outcome that is preventable. This guide explains what jaundice in babies looks like, how it is tested and treated, how to tell if jaundice is getting better, and when to call.
Key Takeaways
Jaundice in babies is common and usually mild, but the eye cannot judge a bilirubin level.
Every newborn should have a bilirubin measurement before leaving the hospital (AAP).
Frequent feeding helps. Sunlight, water and sugar water are not treatments.
There is no single safe number: thresholds depend on age in hours, gestational age and risk factors.
Call the same day for jaundice in the first 24 hours, yellow on the belly, arms or legs, poor feeding or pale stools.
Table of Contents
Baby Jaundice at a Glance
Quick Answer
Baby jaundice is yellowing of a newborn’s skin and the whites of the eyes from a buildup of bilirubin. It is usually noticeable at 2 to 4 days old and most often goes away within 2 weeks, though it commonly lasts a month or longer in breastfed babies. Call the doctor for yellowing in the first 24 hours, yellow on the belly, arms or legs, poor feeding, or a baby who is hard to wake.
Bilirubin is a yellow substance the body creates when it replaces old red blood cells (MedlinePlus). Before birth, the mother’s liver removes it. After birth, it takes a few days for a baby’s liver to get better at the job (AAP), and newborns also produce more bilirubin than adults do (Mayo Clinic).
How Common Is Newborn Jaundice, and How Long Does It Last?
The CDC says about 60% of all babies have jaundice, and StatPearls (NIH) estimates approximately 60% of term and 80% of preterm newborns in the first week.
Baby
When it usually shows
When it usually clears
Full-term
Noticeable at 2 to 4 days (MedlinePlus); bilirubin is usually highest at 3 to 5 days (CDC)
Within 2 weeks (MedlinePlus); by 2 to 3 weeks (StatPearls)
Formula-fed
First days of life
Most goes away by 2 weeks (AAP)
Breastfed
First days of life; breast milk jaundice may appear after day 7 (MedlinePlus)
Commonly lasts 1 month or occasionally longer (AAP)
Preterm (before 37 weeks)
More likely; may not process bilirubin as quickly (Mayo Clinic)
No single timeline in these sources; more likely to be treated at lower levels (MedlinePlus)
Newborn jaundice timelines.
Because the peak can come after you go home, the CDC stresses a check by a nurse or doctor at 3 to 5 days old.
Types of Jaundice in Babies
Type
Typical timing
What is going on
Physiologic jaundice
Noticeable at 2 to 4 days; usually gone within 2 weeks (MedlinePlus)
A newborn liver that cannot yet remove bilirubin quickly enough (Mayo Clinic)
Baby is not yet getting enough milk, so less bilirubin leaves in the stool (AAP, StatPearls)
Breast milk jaundice
After day 7; likely to peak in weeks 2 and 3; may last at low levels for a month or more (MedlinePlus)
Seen in some healthy, breastfed babies (MedlinePlus)
Blood group incompatibility (Rh or ABO)
Varies; any jaundice in the first 24 hours is tested right away (AAP)
A blood type mismatch between mother and baby; a listed cause of severe jaundice (MedlinePlus)
Other causes
Varies
Bleeding under the scalp, infection, an enzyme deficiency such as G6PD deficiency, and liver or bile duct problems such as biliary atresia (MedlinePlus, Mayo Clinic)
Common types of newborn jaundice.
Symptoms of Jaundice in Babies and How to Check
The AAP says jaundice usually appears first in the face and then moves to the chest, abdomen, arms and legs as the bilirubin level increases.
Use white light: daylight or fluorescent light shows jaundice best (AAP).
Do the press test: press gently on your baby’s forehead or nose. If the skin looks yellow where you pressed, it is likely mild jaundice (Mayo Clinic).
On darker skin tones: jaundice can be harder to see. The CDC says checking the gums and inner lips may detect it, and the whites of the eyes can also look yellow.
The AAP guideline cautions that judging bilirubin by eye is unreliable, so use your check to decide when to call. A baby who is both yellow and very sleepy deserves a call; see our sleepy newborn guide and why newborns sleep so much.
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Under the AAP’s 2022 guideline, for babies born at 35 weeks or later, every newborn is checked visually at least every 12 hours until discharge, and a bilirubin level is measured between 24 and 48 hours after birth, or before discharge if that comes sooner.
Transcutaneous bilirubin (TcB): a light meter placed on your baby’s head (CDC).
Total serum bilirubin (TSB): a small blood sample from the heel (CDC), used when the skin reading is high or near the treatment threshold (AAP).
There is no single safe number. The AAP bases treatment thresholds on gestational age, age in hours, and risk factors for bilirubin-related brain injury. Ask how far your baby’s level is from the treatment threshold for their age.
Follow-up. In most cases, babies discharged before 48 hours should be seen within 2 days (AAP); the guideline ties timing to how close the last level was to the threshold. Babies with a high level, birth more than 2 weeks early, jaundice in the first 24 hours or breastfeeding that is not going well need an earlier visit (AAP). The doctor can check the stump too; see umbilical cord care.
How to Tell if Jaundice Is Getting Better
At home, the reassuring signs are mostly feeding and diapers, because frequent feeding brings frequent bowel movements, which help remove bilirubin (MedlinePlus).
The yellow is not spreading or deepening: jaundice moves from the face down the body as bilirubin rises (AAP). We found no primary source describing the order in which it fades.
Plenty of wet diapers: at least 4 to 6 thoroughly wet diapers in 24 hours (CDC); 6 or more a day by days 5 to 7 for breastfed babies (AAP).
Stools turn yellow: from blackish and tarry on days 1 and 2 to yellow and loose, at least 3 to 4 times a day, by days 5 to 7 in breastfed babies (AAP). See our baby poop color guide.
The number is falling: only a repeat bilirubin test confirms improvement, so keep every follow-up visit.
Supplementing: in some babies, supplementing breast milk with formula can help lower the bilirubin level (AAP). Ask your provider first (MedlinePlus). Our triple feeding guide explains nursing, pumping and topping up.
Phototherapy: babies are placed undressed under special lights (AAP), wearing a diaper and eye shades; breastfeeding should continue if possible (MedlinePlus). It is typically done in the hospital but can sometimes be done at home (AAP).
Exchange transfusion: very high levels are a medical emergency that might require intensive care and a special type of blood transfusion (AAP).
What Does Not Treat Baby Jaundice: Sunlight, Water and Sugar Water
Sunlight. The AAP says putting your baby into sunlight is not a safe way to treat jaundice, and the CDC says the same. Water or sugar water. The AAP guideline states that oral supplementation with water or dextrose (sugar) water should not be provided to prevent high bilirubin or to bring it down.
Risk Factors, and Why Severe Jaundice Matters
Being born before 37 weeks (CDC, Mayo Clinic)
Jaundice in the first 24 hours, or a level close to the treatment threshold before discharge (AAP)
A mother with type O or Rh negative blood (CDC); G6PD deficiency in the baby (AAP)
A parent or sibling who needed light therapy (AAP)
Breastfeeding with low milk intake (AAP)
Bruising at birth or bleeding under the scalp (CDC, AAP)
An East Asian or Mediterranean family background (CDC)
The CDC explains that when severe jaundice goes untreated for too long, it can cause kernicterus, a type of brain damage. It is rare: StatPearls estimates acute bilirubin encephalopathy, the early stage, at approximately 1 in 10,000 live births. And it is preventable: the CDC states that early detection and management of jaundice can prevent kernicterus.
Jaundice Lasting More Than 2 or 3 Weeks, Pale Stools or Dark Urine
Tell the doctor if jaundice lasts more than 2 weeks in a formula-fed baby or longer than 4 weeks in a primarily breastfed baby (AAP). The 2022 guideline has clinicians measure direct (conjugated) bilirubin in breastfed babies still jaundiced at 3 to 4 weeks and formula-fed babies at 2 weeks.
The purpose is to catch liver and bile duct problems such as biliary atresia. The AAP says affected babies appear healthy at first; by 4 to 6 weeks, jaundice and pale stools develop and urine may appear dark. StatPearls says it classically presents around 2 to 4 weeks. If a jaundiced baby has pale stools or dark urine, call that day.
Call 911 or go to the emergency room if your baby is crying inconsolably or with a high pitch, is arched like a bow, has a stiff, limp or floppy body, or has strange eye movements (CDC). MedlinePlus also calls jaundice an emergency if the baby has a fever, has become listless, or is not feeding well. If you are unsure, call.
Frequently Asked Questions
How long does baby jaundice last?
The American Academy of Pediatrics says most jaundice goes away by 2 weeks in formula-fed babies, while in breastfed babies it commonly lasts 1 month or occasionally longer. Tell your baby’s doctor if jaundice lasts beyond those points, or if it worsens.
How can I tell if jaundice is getting better?
Reassuring signs are yellow color that is not spreading or deepening, a baby who feeds at least 8 to 12 times a day, plenty of wet diapers, and stools turning yellow. Only a repeat bilirubin test confirms improvement, so keep follow-up visits.
Does sunlight help newborn jaundice?
No. The American Academy of Pediatrics says putting your baby into sunlight is not a safe way to treat jaundice, and the CDC agrees. When treatment is needed, doctors use phototherapy with special lights, in the hospital or sometimes at home.
What bilirubin level is dangerous for a newborn?
There is no single number. Under the American Academy of Pediatrics 2022 guideline, treatment thresholds depend on the baby’s gestational age, age in hours, and risk factors. Ask the doctor how close the level is to the treatment threshold for your baby’s age.
Can I keep breastfeeding if my baby has jaundice?
In most cases, yes. The American Academy of Pediatrics advises breastfeeding at least 8 to 12 times a day in the first few days, and MedlinePlus says breastfeeding should continue during phototherapy if possible. Ask your pediatrician before changing feeds.
How do I check for jaundice on darker skin?
Jaundice can be harder to see in babies with darker skin color. The CDC says checking the gums and inner lips may detect it, and the whites of the eyes can also look yellow. Check in daylight. A bilirubin test is what counts.
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