Infant jaundice (yellowing of the skin) is a common and typically harmless condition in babies.

It’s quite usual for a baby’s bilirubin level to rise above 5 mg/dL (milligrams per deciliter) within the first few days after birth.

If the levels get too high, however, it can cause concern for parents and care providers.

In this article, we explore what a baby’s normal bilirubin levels are, as well as the tests and treatment used to manage high levels.

What is bilirubin?

Bilirubin is a substance the body makes during the breakdown of red blood cells. As the red blood cells break down, bilirubin is processed in the liver and then excreted from the body in urine or stool.

Infant jaundice occurs when bilirubin isn’t removed from the body fast enough and builds up, causing yellowing of the skin (the yellow substance present in bilirubin makes the newborn babies have yellow skin). If the total serum bilirubin level is high the yellow color may affect the eyes.

In most cases of jaundice, no treatment is needed. It usually appears at some time in the first week after birth and disappears, without treatment, after a few weeks. This is called physiologic jaundice and it’s quite common in the first week of life.

A few babies can become severely jaundiced. These cases need investigation and treatment to prevent possibly serious complications from developing.

Is it common for newborns to have jaundice?

Mild jaundice occurs in about 60% of full-term newborns, and in up to 80% of premature babies (babies born before week 37 of pregnancy).

To understand jaundice in newborns, it’s important to know there are different forms of jaundice. Jaundice is also more or less serious depending on the baby’s age.

Here are three types of newborns jaundice:

Physiologic jaundice

This occurs as a result of a high concentration of red blood cells and immature liver function.

It usually appears in the first week of life and resolves in 1-2 weeks (3 weeks if the baby is premature). As the number of red blood cells drops, the jaundice resolves.

This type isn’t associated with underlying diseases or disorders.

Pathological jaundice

This is always considered if jaundice develops in the first 24 hours after birth, if the bilirubin level is very high from the first 24 hours to 10 days after birth, or if the infant shows signs of serious illness.

Breastfeeding jaundice

This occurs 5-7 days after birth, typically peaks at 14 days, and can last as long as a few months. It’s thought to be caused by an increased concentration of an enzyme (beta-glucuronidase) found in breast milk.

Breast milk jaundice is common in breastfed babies and is normal.

Breastfeeding jaundice can sometimes happen because breastfeeding isn’t well established.

Always make sure your breastfed baby gets enough breast milk; sometimes a baby develops neonatal jaundice because she’s experiencing some kind of trouble breastfeeding.

Formula-fed babies don’t develop jaundice as frequently as breastfed babies.

What are the normal bilirubin levels for newborns?

Almost all babies have higher bilirubin levels within 1-2 days of birth.

Newborn jaundice (neonatal hyperbilirubinemia) is diagnosed when blood levels of bilirubin are over 5mg/dL.

Here is some information about bilirubin levels, according to the American Academy of Family Physicians:

Physiological jaundice in healthy term babies usually sees bilirubin levels of about 5-6mg/dL on day 4 after birth; they drop over the next week until they reach normal levels
Newborns with multiple risk factors might also develop an exaggerated form of physiological jaundice, with bilirubin levels as high as 17mg/dL
Breast milk jaundice develops in about 30% of healthy breastfed babies, around 5 days after birth. Levels are between 12-20mg/dL
Pathological jaundice is the appearance of jaundice within 24 hours after birth, a rising level of more than 5mg/dL per day, and bilirubin levels higher than 17 mg/dL in a full-term baby. A number of disorders, such as biliary atresia, can cause pathological jaundice.

Newborn jaundice is common and rarely poses a health risk to your baby. However, if jaundice occurs, it’s important to monitor it and talk to your doctor.

For more information, make sure you read Jaundice In Newborns – The Truth About Jaundice.

What is a dangerous level of bilirubin in newborns?

Although it’s common for the bilirubin level to be high in newborns, if levels are 20mg/dL or more, severe jaundice (hyperbilirubinemia) is diagnosed.

Research shows that less than 2% of babies will develop severe hyperbilirubinemia.

These are the main factors your baby’s healthcare provider will consider:

How old your baby is and how many hours/days after birth jaundice develops
How fast the level is rising
What your baby’s gestational age was and whether your baby was born early (premature).

There are two forms of bilirubin that are measured by laboratory tests; they determine the cause, treatment, and management of hyperbilirubinemia in newborns:

Indirect or unconjugated bilirubin. During the breakdown of red blood cells, bilirubin is formed and is then carried by proteins to the baby’s liver. Small amounts might be present in the baby’s blood test
Direct or conjugated bilirubin. This is formed in the liver when bilirubin combines with sugars (conjugated), enters the bile, and is eventually eliminated in the stool.

When is treatment for newborn jaundice necessary?

Jaundice will usually cause yellowing of the skin, eyes or body. Your doctor might recommend testing for high levels of bilirubin.

There are two ways to test a baby’s bilirubin:

Bilirubinometer (skin test). This is a device that beams light onto your baby’s skin. The meter analyses how the beams of light are reflected off the skin, or absorbed by the skin. It then calculates the level of bilirubin in the blood cells, potentially picking up hyperbilirubinemia in the newborn
Blood test. This is done by the baby’s healthcare provider. A sample of blood is obtained by pricking your baby’s heel with a needle to get drops of blood. The level of bilirubin in the liquid part of the blood (the serum) is measured and then checked to to see whether the serum bilirubin is elevated.

Treatment is recommended if your baby’s bilirubin levels reach:

15mg/dL in newborns 25-48 hours old
18 mg/dL in newborns 49-72 hours old
20 mg/dL in newborns older than 72 hours.

How can I lower my baby’s bilirubin?

There are different treatments for infant jaundice, depending on its cause and severity.

Based on the results of your baby’s tests, you might choose:

Enhanced nutrition. To prevent weight loss, it’s recommended you frequently breastfeed or supplement feed to ensure your baby receives adequate nutrition. This also helps your baby eliminate bilirubin and avoid a possible urinary tract infection
Light therapy (phototherapy). Your baby is placed under a special lamp that emits light in the blue-green spectrum. The light changes the shape and structure of bilirubin molecules so they’re moved out, both in urine and bowel movements
Intravenous immunoglobulin (IVIg). Jaundice could be related to blood type differences – that is, between the mother’s blood type and the baby’s blood type (e.g. ABO incompatibility). This results in the baby carrying antibodies from the mother, which contribute to the rapid breakdown of the baby’s red blood cells. When the mother’s antibodies come into contact with one of the baby’s red blood cell they will attack it and break it down, releasing bilirubin. This is called hemolytic disease
Exchange transfusion. Rarely, severe jaundice doesn’t respond to other treatments and infants might need an exchange transfusion of blood. An exchange transfusion involves a staged blood transfusion, which means repeatedly withdrawing small amounts of the baby’s blood and replacing it with fresh donor blood, diluting the serum bilirubin and the maternal antibodies. An exchange transfusion isn’t often necessary, as hemolytic disease of the newborn is quite rare. If your baby’s serum bilirubin level causes such high neonatal hyperbilirubinemia that your baby needs an exchange transfusion, your baby’s healthcare providers will be able to help you. They will provide information and support during the whole process until her serum bilirubin returns to normal.

You can read more about hemolytic disease in Rhesus Factor And Pregnancy: A Must Read If You Have Rh- Blood.

What is kernicterus in neonatal jaundice?

In rare cases, too much bilirubin (unconjugated hyperbilirubinemia) builds up. This bilirubin level can be toxic and can damage developing brain cells, leading to a type of brain damage called kernicterus.

Facts about kernicterus:

Premature babies and full-term babies who have risk factors can develop kernicterus at lower levels of bilirubin than healthy full-term babies. If you have a premature baby your baby’s healthcare provider will keep an extra eye on your baby’s bilirubin level
Long-term effects of kernicterus are learning and developmental disabilities, hearing loss, movement problems, eye movement problems. It can also result in death
The exact level linked to kernicterus in a healthy full-term newborn is unknown. The occurrence is rare, developing in 1 in every 100,000 babies
There are several factors that influence the toxicity of the brain, such as ethnicity, underlying disease, and how old the baby is.

What should a mother eat if a baby has jaundice?

When it comes to jaundice and breastfeeding, your diet matters. You can help your baby’s liver to process and remove bilirubin by eating the right foods.

Some foods that can help do this are:

Foods that are high in fiber
Papaya and mango
Milk thistle tea
Fresh vegetables
Multigrain bread
Tofu
Salmon

You should also drink plenty of water.

Make sure you and your baby get all the nutrients you need. This allows the liver to function more effectively. It might also improve the color of your baby’s skin.

Do jaundiced babies sleep more?

In some cases of jaundice, a high bilirubin level can make your baby lethargic and sleepy. This leads to a baby being less interested in feeding, which in turn can lead to higher levels of bilirubin, as a result of dehydration.

It’s important to encourage your baby to feed often; this will lower the levels of bilirubin.

Why do breastfed babies get jaundiced?

Breastfeeding jaundice in newborns is rare, occurring in fewer than 3% of infants. It often runs in families. Usually, it doesn’t cause any problems and goes away on its own.

The exact reason why this condition occurs isn’t known, although it’s thought the mother’s breast milk contains a substance that prevents her baby’s liver from breaking down bilirubin.

While baby is inside the uterus, the placenta removes bilirubin very efficiently from the baby’s body. Once the baby is born, neonatal hyperbilirubinemia is quite common in the newborn, especially in the breastfed newborn.

Does sunlight help newborn jaundice?

You might have heard that sunlight can help treat jaundice in newborns. Although it might sound like an old wives’ tale, there’s a bit of science in this method.

Filtered sunlight helps to break down the bilirubin, so your baby can excrete it through urine and bowel movements.

A study showed that filtered sunlight (under special canopies) on a baby’s body was as effective in reducing bilirubin as conventional phototherapy.

Filtering sunlight cuts out the harmful ultraviolet and infrared rays that cause sunburn and overheating. It mimics phototherapy lamps that emit blue wavelengths and which are normally used in hospitals.

To use sunlight to treat newborn jaundice, put your baby near a well-lighted window for 10 minutes twice a day. Don’t put your baby in direct sunlight.

When infants receive phototherapy, the aim is to produce the same effect as if the baby were exposed to sunlight. Treating jaundice in this way, however, ensures all safety measures are in place. While under intensive phototherapy, the baby’s eyes are protected with a type of eye mask attached to the baby’s forehead. The latest models of intensive phototherapy devices are in direct contact with the baby’s skin. They are in the form of a fiber optic blanket with tiny bright lights, which is wrapped around the baby’s body. This way the light therapy is applied directly to the baby’s skin and the eyes get hardly any phototherapy.

Newborn baby jaundice level chart

Although a baby’s country of origin has little to do with excess bilirubin, each country has slightly different charts for jaundice in newborns. We’ve gathered the data of the total serum bilirubin for jaundiced newborns in Australia, USA and the UK. Here are the cut off points in these countries for babies to be considered to have clinical jaundice. Baby’s jaundice depends a lot in how many hours old a baby is.

Normal bilirubin levels in newborns in Australia/USA/UK

Australia

Total serum bilirubin level, by age of baby (hours old): bilirubin measurement (micromole/liter)

Less than 24hrs: above 200
24-48hrs: above 260
49- 72hrs: above 320
More than 72hrs: above 350

USA:

Total serum bilirubin level, by age of baby (hours old): bilirubin measurement (micromole/liter)

Less than 24 hrs: above 180
24-48 hrs: above 270
49-72 hrs: above 324
More than 72 hrs: above 360

UK:

Total serum bilirubin level, by age of baby (hours old): bilirubin measurement (micromole/liter)

6hrs: above 125
12hrs: above 150
18hrs: above 175
24hrs: above 200

Signs of recovery from jaundice in newborns

When your newborn baby is recovering from hyperbilirubinemia, you’ll see that the yellow color in the eyes disappears. It also begins to fade in the skin as the amount of serum bilirubin decreases.

Your baby will be less sleepy and will spend more time happily awake.

The stools, which are usually green, due to the high amount of bilirubin in them, will start having normal consistency and color, appropriate to your baby’s age.

You can read more about this in 11 Types Of Baby Poo And What They Mean.