What is jaundice?

Jaundice in newborns is common. It can make your baby’s skin and the whites of their eyes go yellow. Mild jaundice occurs in about half of full-term newborns, and is more common in premature babies. You’re most likely to notice it from the third day after birth.

Jaundice is usually harmless and disappears in 1 to 2 weeks. But all cases of jaundice in newborn babies should be checked by a doctor or nurse.

What are the common causes of jaundice in newborns?

When red blood cells break down, a chemical called 'bilirubin' is released, this makes the skin go yellow. Newborn babies are born with (and need to break down) a lot of red blood cells but their liver isn't yet developed enough to process the bilirubin. This results in a bilirubin overload, leading to jaundice. By about 2 weeks, your baby's liver is more developed and will be better at removing bilirubin.

Most newborns with jaundice will have 'breast milk jaundice'. This type of jaundice usually sorts itself out without treatment, after several weeks. You do not need to stop breastfeeding.

Rare causes of jaundice in newborns

One rare type of jaundice occurs when the mother's and the baby's blood groups are incompatible (usually ABO or Rhesus factor incompatibility). This isn't usually a problem during a first pregnancy because the mother's and the baby's bloodstreams don't mix. But during the birth, some of the baby's blood might mix with the mother's blood.

The mother then develops antibodies that become active during the next pregnancy and cross the placenta to attack a second baby's red blood cells. The destruction of the red blood cells causes more bilirubin to be released into your second baby's bloodstream, leading to jaundice. This type of jaundice is usually seen in the first 24 hours after birth.

Biliary atresia is another rare cause of jaundice in babies. It happens when the tiny tubes that carry bile from the liver to the intestine get scarred. Babies with this condition usually grow normally and look well at first, but they will get very ill with serious liver disease if they aren't diagnosed and treated early. Their jaundice will usually go on after they are 2 weeks of age, and they might also have pale-looking poo.

What are the symptoms of jaundice?

Jaundice in a newborn will cause their skin and the whites of their eyes to go a yellow colour. It typically starts on the face and head. If the level of bilirubin increases, the colour will spread down to the body. Some babies might also be drowsy and have difficulty feeding.

When should I see my doctor?

Jaundice is usually harmless, but a nurse or doctor should check and monitor all cases of jaundice in newborn babies. You should take your baby to the doctor if:

• your baby is unwell, feeding poorly and not gaining enough weight
• your baby's poo becomes pale or their wee becomes dark
• your baby develops jaundice in the first 48 hours after birth
• the jaundice becomes more noticeable after a week
• the jaundice hasn't gone away after 2 weeks

What are the tests for jaundice?

If your baby has jaundice lasting more than 2 weeks — especially if their poos are pale or their wees are dark — they'll need a blood test to check the 'conjugated bilirubin' levels in the blood. They might then need more tests on their liver.

How to treat normal jaundice

Treatment for jaundice in newborns depends on how bad it is and what has caused it.

If your baby has mild jaundice, the treatment is simple — they just need to have enough fluids, so ensure they are breast or formula fed regularly.

Babies who develop jaundice several days after birth usually just need careful monitoring, sometimes with heel prick blood tests, to check the bilirubin levels in their blood.

If the bilirubin levels are high, your baby might need to have phototherapy treatment. Phototherapy is treatment with a special kind of blue light that helps your baby’s liver to breakdown the bilirubin more easily. This treatment is very easy and safe.

Sometimes your baby is treated with phototherapy wrapped in a special blanket or sometimes in a cot with blue lights and their eyes covered for protection.

Phototherapy has minimal side effects. Sometimes your baby might have a mild rash and/or runny poo for a few days. Some babies might need extra feeds during this time. Most babies tolerate phototherapy treatment well.

In some cases, phototherapy is only needed for 24 hours or less, in other cases, it may be required for a few days.

If your baby has breast milk jaundice, you do not need to stop breastfeeding. This type of jaundice is usually mild and should get better by itself with time. Talk to your child health nurse or doctor if you're worried about what to do.

How to treat serious jaundice

Severe jaundice, in which bilirubin levels are very high, might need treatment with an exchange blood transfusion. This is when a baby’s own blood is replaced with compatible fresh blood. This isn’t common. Severe jaundice can very occasionally lead to deafness and even brain damage if not treated promptly.