Newborn Jaundice: What Parents Need to Know About Causes and Care

Newborn jaundice is very common in the first days of life. It causes a yellow color in the skin and the whites of the eyes because of a substance called bilirubin. In many babies, jaundice is mild and improves as the baby feeds, stools, and the liver matures. However, some babies need close monitoring or treatment because very high bilirubin levels can be dangerous.

Understanding what is normal, what needs a call to the doctor, and how jaundice is checked can help parents feel less anxious during the first week at home.

What causes newborn jaundice?

Bilirubin is produced when the body breaks down old red blood cells. Newborns naturally have a higher turnover of red blood cells, and their livers are still learning to process bilirubin efficiently. This combination makes jaundice common.

The most common type is physiologic jaundice. It often appears around day 2 or 3, peaks around day 3 to 5, and gradually improves. Premature babies may have jaundice for longer because their bodies are less mature.

Other causes can include:

• Not getting enough milk in the first days of life
• Blood type incompatibility between parent and baby
• Bruising from birth
• Prematurity
• Infection
• Certain inherited red blood cell or enzyme conditions
• Liver or bile duct problems, which are less common but important

Because causes vary, bilirubin should be assessed by a healthcare professional rather than judged by appearance alone.

How to recognize jaundice

Jaundice often starts on the face and then moves down the chest, belly, arms, and legs as bilirubin rises. It may be easier to see in natural light. In babies with darker skin tones, yellowing may be more noticeable in the whites of the eyes, gums, or inside the mouth.

Parents may notice:

• Yellow skin or yellow eyes
• Sleepiness or difficulty waking for feeds
• Poor feeding
• Fewer wet or dirty diapers than expected
• Dark yellow urine
• Pale, gray, or white stools

Visual checks are not enough to measure severity. A baby can look only mildly yellow and still have a bilirubin level that needs follow-up, especially if risk factors are present.

How doctors check bilirubin

Bilirubin can be measured with a skin device called a transcutaneous bilirubin meter or with a blood test. Your baby’s age in hours matters because the meaning of a bilirubin number changes over time. A level that is acceptable at one age may need treatment at another.

Many hospitals check jaundice before discharge. Babies who go home early may need a follow-up visit within a few days. Keep all newborn appointments, even if your baby seems well.

Feeding and jaundice

Frequent feeding helps babies pass bilirubin through stool and urine. In the first days, breastfed newborns usually feed often—commonly 8 to 12 times in 24 hours. Formula-fed babies also need regular intake based on age and medical guidance.

Call your baby’s clinician if your baby is hard to wake, feeds weakly, has fewer diapers than expected, or seems increasingly yellow. If breastfeeding is difficult, ask for help early. Lactation support can make a big difference.

Do not give water, sugar water, herbal remedies, or sunlight treatment at home unless your clinician specifically instructs you. These approaches can delay proper care or create safety risks.

Phototherapy treatment

Phototherapy uses special blue light to help break down bilirubin in the skin so the baby can remove it more easily. The baby wears eye protection and is placed under the light for a prescribed amount of time. Feeding usually continues during treatment.

Some babies receive phototherapy in the hospital; others may be treated at home with medical supervision if the bilirubin level and risk factors allow it. Severe cases may require more intensive treatment, but this is less common when jaundice is monitored early.

When to call a doctor urgently

Contact your pediatrician or seek urgent care if:

• Your baby looks very yellow or the yellow color spreads to the legs
• Your baby is very sleepy, limp, or difficult to wake
• Feeding is poor or your baby refuses feeds
• There are fewer wet diapers than expected
• Urine is dark or stools are pale, gray, or white
• Jaundice appears in the first 24 hours after birth
• Your baby has a fever or seems ill
• Your baby has a high-pitched cry, unusual movements, or arching of the body

These signs need prompt medical evaluation.

FAQ

Is newborn jaundice always dangerous?

No. Many cases are mild and temporary. The concern is when bilirubin rises too high or increases quickly, which is why monitoring matters.

Can I treat jaundice by placing my baby near a window?

Do not rely on sunlight through a window. It is not a safe or reliable treatment and may delay proper care. Follow your clinician’s advice.

Does breastfeeding cause jaundice?

Breastfeeding itself is not “bad.” Some babies develop jaundice when intake is low in the first days. Frequent feeding and lactation support can help. A clinician can guide you if supplementation is needed.

How long does jaundice last?

Many babies improve within 1–2 weeks. Breastfed babies may have mild jaundice longer. Persistent or worsening jaundice should be checked.

References

• American Academy of Pediatrics. Clinical Practice Guideline Revision: Management of Hyperbilirubinemia in the Newborn Infant 35 or More Weeks of Gestation.
• Centers for Disease Control and Prevention. Jaundice and Kernicterus information for families.
• MedlinePlus. Newborn jaundice.

If jaundice seems to worsen, feeding is poor, or your newborn is hard to wake, contact your pediatrician right away rather than monitoring it at home for too long.