Newborn Jaundice: Causes, Signs and Treatment

Newborn jaundice is a yellow colour of the skin and eyes that many babies have in the first week of life. In most babies it is harmless and fades by itself within about two weeks.

Still, some babies need treatment, and a few have jaundice that points to another problem. This guide explains the difference, the signs to check at home, what phototherapy is, and when to call a doctor.

What causes jaundice in newborns?

Jaundice happens when a yellow substance called bilirubin builds up in the blood. Bilirubin is made when old red blood cells break down. A newborn’s liver is not yet mature enough to clear it quickly, so levels rise for a few days. Cleveland Clinic says this affects up to 60 percent of full-term babies and up to 80 percent of premature babies in the first week.

The NHS adds that in most babies jaundice is not a sign of another health problem.

Normal jaundice versus jaundice that needs checking

Doctors often separate jaundice into the usual kind and kinds that need a closer look. The words differ between sources, so here is a simple guide.

Usual (physiological) jaundice

• Appears around day 2 or 3 of life.
• Bilirubin usually peaks at 3 to 5 days.
• Usually clears within about two weeks.
• The baby feeds well, wakes for feeds and has normal wet and dirty nappies.

Breastfeeding-related jaundice

• Breastfeeding jaundice can happen in the first week when a baby is not getting enough milk, for example because of latch problems or because the milk is slow to come in. It may take longer to settle.
• Breast milk jaundice usually appears after the first week and can last a month or more, as substances in breast milk affect how bilirubin is broken down.
• Neither means you should stop breastfeeding. Ask for feeding help; our guide to breastfeeding problems explains the common fixes.

Jaundice that needs investigation

Some causes are less common and need a doctor’s tests. Cleveland Clinic lists blood infection, a blood group mismatch with the mother, bruising from a difficult birth, too many red blood cells, low oxygen levels and liver conditions. The NHS also mentions Gilbert’s syndrome and infections such as rubella. Jaundice in the first 24 hours of life is always treated as urgent. Read about Rh-negative blood group in pregnancy if you know your blood group is negative.

How to check your baby for jaundice at home

• Look in bright natural light, such as near a window.
• Yellowing usually starts on the face and head, then spreads to the chest, tummy, arms and legs as bilirubin rises.
• Check the whites of the eyes and under the tongue, as these show yellow too.
• On brown or dark skin it can be hard to see on the skin, so the eyes, gums and tongue are more reliable.

Tip: Jaundice is easier to miss at home than in hospital. Look at your baby in daylight each day for the first two weeks, and write down how many wet and dirty nappies there are.

How is jaundice tested?

• Skin test (transcutaneous bilirubin): a small device placed on the baby’s head estimates the bilirubin level without a needle.
• Blood test (serum bilirubin): a heel-prick blood test confirms a high skin reading and guides treatment.
• Other tests: if something more serious is suspected, doctors may check blood groups, do urine or liver tests, or arrange an ultrasound.

Doctors use the baby’s age in hours or days together with the bilirubin level to decide if treatment is needed. A level that is fine on day 2 may need action on another day, so do not compare numbers with other babies.

Treatment: feeding, phototherapy and rarely more

Most babies need no treatment. The NHS says that frequent feeds, around 8 to 12 times a day, help the baby get rid of bilirubin. Wake a sleepy baby for feeds and ask for help if feeding is hard.

If bilirubin is high or still rising, the usual treatment is phototherapy:

• The baby is undressed, apart from a nappy, and an eye mask protects the eyes.
• Special blue light shines on the skin. This helps the body break down bilirubin.
• The NHS says most babies need about 48 hours, while Cleveland Clinic describes one to two days. It is generally considered safe, and some babies with mildly raised levels may be treated at home.
• Feeding continues,, and bilirubin is rechecked to see how treatment is working.

Rarely, when bilirubin stays dangerously high, a blood transfusion in which some of the baby’s blood is replaced is needed in hospital. Untreated, very high bilirubin can affect the brain, which is why timely treatment matters.

When to be cautious: Do not wait to see if jaundice settles if your baby is under 24 hours old, very sleepy, feeding poorly or getting more yellow. Jaundice that looks mild at home can still need a blood test.

When to see a doctor

The NHS advises seeking urgent advice from a doctor or midwife if your baby is over 24 hours old and the jaundice is getting worse or not improving, or if the urine is dark yellow or brown or the stools are pale or creamy. Cleveland Clinic also lists jaundice that lasts longer than two weeks, a brighter yellow or orange colour, fewer wet or dirty nappies and poor feeding.

Get emergency help straight away if your baby with jaundice:

• Is very sleepy, hard to wake or will not feed
• Is floppy, stiff, arching the back or twitching
• Has a high-pitched cry
• Has a fever or a low temperature, or breathing problems
• Has no wet nappies
• Is less than 24 hours old

Do not drive yourself if you are alone and distressed; ask someone to drive. Our emergency and critical care speciality provides 24/7 emergency support for mothers and newborns; see the emergency page.

Follow-up and newborn care

Because bilirubin usually peaks at 3 to 5 days, a follow-up bilirubin check in the first week matters, as Cleveland Clinic advises. Our postnatal and newborn care speciality covers postnatal recovery and breastfeeding support. See also newborn feeding schedule and hunger cues and newborn care tips for first-time parents.

Talk to a doctor

If you have questions about newborn jaundice or your baby’s feeding, you are welcome to book an appointment or call +91 944 103 0587. Chaitanya Hospital is in Kadapa, near RTC Bus Stand, Simhapuri Colony, and teleconsultation is also available. This article is for general awareness and is not a substitute for a doctor's advice.