What is a good number for jaundice in newborns?

Jaundice in newborns happens when there’s an overload of bilirubin in a baby’s blood. This can make the baby’s skin and eye whites go yellow.

Bilirubin is a waste product that’s produced when old red blood cells break down. Usually, the liver processes bilirubin and mixes it into bile. Bile then goes from the liver to the digestive tract and finally comes out of the body in poo. In newborns, several things can stop this happening properly, which leads to a bilirubin overload.

Types of jaundice in newborns

Physiological jaundice
In physiological jaundice, babies’ livers aren’t yet developed enough to get rid of bilirubin.

This type of jaundice is very common in newborns. It usually gets better when your baby’s liver is mature enough to process bilirubin properly.

Breastmilk jaundice
Breastfed babies often get breastmilk jaundice. This is when a chemical in the mother’s breastmilk interferes with the baby’s ability to get rid of bilirubin. This type of jaundice often happens a few days after birth.

Breastmilk jaundice isn’t harmful and usually sorts itself out after several weeks.

Breastfeeding jaundice
Breastfeeding jaundice happens when babies get dehydrated because of problems with breastfeeding. They need fluids to reduce bilirubin levels.

Breastfeeding jaundice usually gets better when babies get more fluids.

Jaundice from delayed cord clamping or delivery interventions at birth
Babies can get jaundice if there’s been a delay in getting their umbilical cord clamped and cut. Delayed clamping can cause there to be too many red blood cells in a baby’s blood. It means that there are more red blood cells than normal for the liver to process, so the bilirubin builds up.

Jaundice can also happen because of interventions during delivery that cause bleeding and bruising – for example, a forceps birth. The red blood cells from this break down and bilirubin builds up.

Blood type incompatibility jaundice
One rare type of jaundice happens when the mother’s and the baby’s blood groups are incompatible.

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 delivery, some of the baby’s blood might mix with the mother’s blood. The mother then develops antibodies that become active during her next pregnancy and cross the placenta to attack a second baby’s red blood cells.

The destruction of these red blood cells in the second baby releases bilirubin into that baby’s bloodstream, which results in jaundice. If this happens, you usually see it in the first 24 hours after birth.

Babies with this kind of jaundice need treatment.

Biliary atresia
Biliary atresia is a rare cause of jaundice in babies.

It happens when the tiny tubes that carry bile from the liver to the intestine don’t work. Babies with this condition usually grow normally and look well at first, but they get very ill with serious liver disease if they aren’t diagnosed and treated early.

Babies with this kind of jaundice usually start to show signs around 2-8 weeks of age.

Babies with this kind of jaundice need surgical treatment.

Symptoms of jaundice in newborns

Newborn jaundice causes your baby’s skin and the whites of their eyes to go a yellow colour. The jaundice typically starts on the face and head.

If the level of bilirubin increases, the colour spreads to the body. Babies might also be drowsy and have feeding difficulties.

Babies with biliary atresia also have pale-looking poo and darker urine.

Does your newborn need to see a doctor about jaundice?

Yes. Your child and family health nurse, midwife, GP or paediatrician should check and monitor your newborn for jaundice.

You should take your baby to the GP if your baby:

• is unwell, feeding poorly and not gaining enough weight
• has pale poo or dark wee
• looks jaundiced.

Tests for jaundice in newborns

Medical staff might measure the level of your baby’s jaundice using a bilirubinometer, which is a special machine that’s briefly placed on your baby’s skin. But they might also need to do a heel prick test to get a more accurate measurement of the level of bilirubin in your baby’s blood.

Sometimes if the levels of jaundice are high or medical staff are worried that your baby has a more serious condition, your baby will need other tests to find the cause.

Treatment of jaundice in newborns

Treatment for newborn jaundice depends on how serious it is and what has caused it.

Physiological jaundice and jaundice from cord clamping or delivery interventions
Babies who develop jaundice several days after birth usually just need careful monitoring. These babies don’t usually have to stay in hospital.

If your baby’s bilirubin levels are high, they might have phototherapy treatment for a few days. This treatment uses a special type of blue light that helps break down the bilirubin overload. Your baby will be placed naked in a cot under a phototherapy lamp for 2-3 days.

Most babies cope with phototherapy treatment well. Phototherapy has minimal side effects, although your baby might have a mild rash and runny poo for a few days. Some babies have small fluid losses during phototherapy, so they might need extra feeds.

Breastmilk jaundice
If your baby has breastmilk jaundice, it doesn’t mean that you need to stop breastfeeding. This type of jaundice is usually mild and should get better by itself with time. Talk with your child and family health nurse or doctor if you’re worried about what to do.

Breastfeeding jaundice
Babies with breastfeeding jaundice get better when they have more feeds. Your child and family health nurse or a lactation consultant can help with breastfeeding.

Severe or blood type incompatibility jaundice
Severe jaundice, in which bilirubin levels are very high, might need treatment with an exchange transfusion. This is when a baby’s own blood is replaced with compatible fresh blood. This is usually a treatment for blood type incompatibility jaundice, but it isn’t common.

Biliary atresia jaundice
If your baby has jaundice caused by biliary atresia, they’ll need an urgent operation to help with bile drainage.

If severe jaundice isn’t treated, it can cause brain damage.

Prevention of jaundice in newborns

Only jaundice caused by a certain type of blood incompatibility is preventable.

If your doctor or health professional thinks this type of jaundice might be a problem, you’ll get an anti-D injection immediately after delivery. This can prevent complications in subsequent pregnancies.

Please note that all guidance is currently under review and some may be out of date. We recommend that you also refer to more contemporaneous evidence in the interim.

Jaundice occurs in approximately 60 per cent of newborns, but is unimportant in most neonates. A few babies will become deeply jaundiced and require investigation and treatment.

If inadequately managed, jaundice may result in severe brain injury or death.

Jaundice early detection is important

Issue to note about jaundice:

• Early detection of jaundice (appears in the sclera with SBR of 35-40 micromol/L) may be difficult in newborns because eyelids are often swollen and usually closed.
• Jaundice may not be visible in the neonate's skin until the bilirubin concentration exceeds 70-100 micromol/L.
• Increasing total serum bilirubin (SBR) levels are accompanied by the cephalocaudal progression of jaundice, predictably from the face to the trunk, extremities and finally to the palms and soles. However, visual estimation of the degree of jaundice may be inaccurate, particularly in darkly pigmented newborns.
• Total SBR level should be used to determine management decisions in cases of predominantly unconjugated hyperbilirubinaemia.
• Serum albumin level does not need to be measured in addition to the bilirubin to determine management.
• SBR from a capillary sample is assumed to be the same as that from a venous sample.
• Sunlight exposure is no longer recommended as a treatment for jaundice due to risk of sunburn or overheating.
   
  
  
  Figure 1: Jaundice in a newborn

Risk factors for developing severe hyperbilirubinaemia

Major risk factors

Major risk factors for severe hyperbilirubinaemia are:

• jaundice within the first 24 hours
• blood group incompatibility; particularly Rhesus (Rh) incompatibility
• previous sibling requiring phototherapy for haemolytic disease
• cephalhaematoma or significant bruising
• weight loss greater than 10 per cent of birthweight; may be associated with ineffective breastfeeding
• family history of red cell enzyme defects (such as G6PD deficiency) or red cell membrane defects (such as hereditary spherocytosis).

Minor risk factors

Minor risk factors for hyperbilirubinaemia are:

Causes of physiological jaundice

Physiological jaundice develops due to:

• increased production
• decreased uptake and binding by liver cells
• decreased conjugation (most important)
• decreased excretion
• increased enterohepatic circulation of bilirubin.
   

As the name implies, physiological jaundice is common and harmless.