Jaundice in newborns Dr Trisha Macnair Jaundice is a common, often temporary and relatively harmless development in newborn babies, but sometimes it's a sign of a more serious problem.

In this article

What is jaundice? Symptoms

Causes and risk factors Treatment/Recovery

Jaundice isn't a disease itself but the name given to the yellow appearance of skin and the conjunctiva (whites) of the eyes.

The yellow colouring is caused by a build-up of the pigment bilirubin in the blood. This is a natural product of the breakdown of red blood cells, which are constantly recycled, and usually cleaned from the blood by the liver.

The liver takes unconjugated bilirubin and converts it into a water-soluble form called conjugated bilirubin. This is filtered into bile, which drains into the gall bladder and passes out of the body through the intestines. Jaundice can result if there's a problem at any stage of this process. Both unconjugated and conjugated bilirubin can cause jaundice.

Jaundice in babies can be concerning as although the majority of causes are easily treated, some rarer causes are very serious. Also, high levels of unconjugated bilirubin can cause brain damage. This is virtually never seen now due to treatment with UVB light, but it means that it is very important that the baby receives proper treatment.

The main symptom of jaundice is yellow colouring of the skin and conjunctiva of the eyes. Jaundice can also make babies sleepy which can lead to poor feeding. Poor feeding can make jaundice worse as the baby can become dehydrated.

If a baby has conjugated jaundice, it may have white chalky stool (poo) and urine that is darker than normal. (The bilirubin that normally colours the stool is excreted in the urine.)

Medical advise should be sought urgently if:

• Jaundice is present in the first 24 hours of life
• Jaundice is present when the baby is 10 days old
• The baby has problems feeding or is very sleepy
• The stools are pale or the urine is very dark

In most cases, jaundice occurs because a newborn baby's liver is inefficient or slow when it first starts to convert bilirubin. This is aggravated by a high turnover of red blood cells in newborns.

As a result, levels of bilirubin can rise quickly in the first few days of life, causing physiological jaundice (not caused by a disease).

This form of jaundice affects up to 65 per cent of babies. It usually settles as the liver gets into action and normally disappears by the time the baby is 10 days old . Breast-fed babies are also likely to become jaundice but be otherwise well.

There are many other possible causes. Bruising during birth happens when bilirubin levels rise as the baby's body breaks down the bruises, and a similar situation occurs when a baby swallows blood during delivery. Infections and other illnesses may also cause jaundice.

Problems with the blood may lead to a rapid breakdown of cells (haemolysis) - if the mother's blood type isn't compatible with her baby's. For example, she may make antibodies that attack and destroy her baby's red blood cells.

Hormone deficiencies such as low levels of thyroid hormone (hypothyroidism) or pituitary gland hormones (hypopituitarism) can trigger jaundice.

There may be inherited genetic problems with the enzymes that convert or break down bilirubin - these include rare conditions such as Crigler-Najjar syndrome, Gilbert's syndrome, galactosaemia and tyrosinaemia.

There may be problems with the liver, such as biliary atresia, in which the tubes that drain bile from the liver are blocked. If spotted early, an operation can prevent long-term damage (which is why it is important to investigate jaundice that is still there at 10 days).

Treatment depends on the cause of the jaundice. Physiological jaundice may not require treatment but if levels of bilirubin are high (determined by a blood test), phototherapy will be required. This involves placing the baby under a special blue light or wrapping them in a light-emitting blanket for a few days.

Sometimes babies need help with their fluid intake as well. Rarely, if the levels of unconjugated bilirubin are very high, the baby may need to have an exchange transfusion which involves taking away some of the baby’s blood and replacing it with a blood transfusion.

This article was last medically reviewed by Dr Orlena Kerek in February 2009