Understanding Normal Jaundice Levels In Newborns

Jaundice is a common condition in newborns, characterised by a yellowing of the skin and eyes due to elevated bilirubin levels in the blood. While it is usually harmless, with mild cases occurring in about 60% of full-term newborns and up to 80% of premature babies, it can sometimes indicate an underlying medical issue. This article will explore what constitutes a normal level of jaundice in newborns and when intervention may be necessary.

What is jaundice?

Jaundice is a condition that causes a yellowing of the skin and eyes. This yellowing is caused by a substance called bilirubin, which is produced when red blood cells break down. While jaundice can affect adults, it is particularly common in newborns, with around 50%-60% of full-term babies experiencing it in the first week of life.

In newborns, jaundice is typically caused by elevated bilirubin levels in the blood, which occur when a baby's immature liver is not yet efficient enough to remove the bilirubin from their bloodstream. This type of jaundice is known as physiological jaundice, and it usually lasts only a few days, disappearing within 1-2 weeks of birth. It typically first appears on the face and then moves down the body. Jaundice can be harder to detect in dark-skinned babies and is best seen in natural light.

While jaundice is generally harmless and resolves on its own, it can sometimes indicate an underlying medical condition. If left untreated, extremely high bilirubin levels (above 25mg) can lead to serious complications such as cerebral palsy, deafness, or brain damage. Therefore, it is important for newborns to be closely monitored for jaundice, and blood tests may be performed to measure bilirubin levels if it is suspected.

There are different types of jaundice, depending on where the bilirubin collects in the body:

• Prehepatic jaundice occurs when bilirubin builds up before blood enters the liver, due to the breakdown of red blood cells creating more bilirubin than the liver can process.
• Hepatic jaundice happens when the liver is unable to process bilirubin effectively.
• Posthepatic jaundice occurs when bilirubin builds up after passing through the liver, and the body cannot clear it quickly enough.
• Obstructive jaundice is caused by a blockage or narrowing of the bile or pancreatic duct, preventing bile from draining into the intestines.

In adults, jaundice is rare but can be caused by various factors such as hepatitis, liver disease, blocked bile ducts, pancreatic cancer, or certain medications. It is often a sign of a problem with the liver, gallbladder, or pancreas. Jaundice may appear suddenly or develop slowly, and treatment depends on the underlying cause.

What are the causes?

Jaundice is caused by elevated bilirubin levels in the blood, also known as hyperbilirubinaemia. Bilirubin is a yellow substance produced when red blood cells, which carry oxygen around the body, are broken down. A newborn baby's liver is not fully developed, so it's less effective at processing the bilirubin and removing it from the blood. This means the level of bilirubin in babies is much higher than in adults.

There are several factors that can cause jaundice in newborns:

• Physiological Jaundice: This is the most common type of jaundice, affecting up to 60% of full-term babies in the first week of life. It occurs due to elevated bilirubin levels caused by the normal breakdown of red blood cells. As the baby's liver matures, it becomes more efficient at removing bilirubin, and the jaundice typically resolves within 1-2 weeks without any lasting effects.
• Breastfeeding or Malnutrition Jaundice: Inadequate intake of breast milk or malnutrition can lead to jaundice in 5-10% of newborns. This can cause poor weight gain and requires close monitoring of weight checks and feedings.
• Breast Milk Jaundice: In some cases, a substance in breast milk can block the removal of bilirubin, leading to jaundice in 10% of newborns. Breast milk intake and weight gain are typically normal in these cases.
• Blood Group Incompatibility: In rare but serious cases, blood group incompatibility between the mother and baby can cause jaundice. This can lead to an increased release of bilirubin from red blood cells and rapid increases in serum bilirubin levels.
• Liver Disease: Liver conditions such as liver infection (hepatitis) or liver blockage (biliary atresia) can cause jaundice. One of the main clues of liver disease is light grey or pale yellow stools.
• Internal Bleeding (Hemorrhage): Internal bleeding can cause jaundice in newborns.
• Infection: An infection in the baby's blood (sepsis) or other viral or bacterial infections can contribute to jaundice.
• Premature Birth: Premature babies, born before 38 weeks of gestation, may have immature livers that are not able to process bilirubin as efficiently as full-term babies. They also tend to feed less and have fewer bowel movements, resulting in reduced elimination of bilirubin through stool.
• Bruising During Birth: Significant bruising during birth can lead to higher levels of bilirubin due to the breakdown of more red blood cells.
• Breastfeeding Challenges: Breastfed babies, especially those who have difficulty nursing or are not getting enough nutrition, are at higher risk of jaundice. Dehydration or low caloric intake may contribute to the onset of jaundice.
• Ethnic Background: Studies indicate that babies of East Asian ancestry, as well as those with Mediterranean ethnic backgrounds, have an increased risk of developing jaundice.
• Genetic Conditions: Genetic conditions such as G6PD (glucose 6 phosphate dehydrogenase) deficiency, an inherited enzyme deficiency, can increase the risk of jaundice or kernicterus.
• Urinary Tract Infection (UTI): In some cases, a UTI in the mother or the baby can be a factor in the development of jaundice.
• Rh Disease: A condition that can occur if the mother has rhesus-negative blood and the baby has rhesus-positive blood, leading to blood type mismatches and a faster breakdown of red blood cells.

It is important to closely monitor newborns for jaundice and seek medical attention if there are any concerns. Most cases of jaundice are mild and resolve without treatment, but in rare cases, severe jaundice can lead to serious complications, including brain damage.

What are the symptoms?

Jaundice is a common condition in newborns, affecting about six out of ten babies to varying degrees. It is caused by a build-up of bilirubin, a yellow pigment of red blood cells, in the baby's blood and tissues. Bilirubin is normally processed by the liver, but a newborn's liver takes a few days to process it, so a mild case of jaundice is not unusual. Physiological jaundice will resolve by itself once the baby's liver is functioning at full speed.

The symptoms of jaundice in newborns include:

• A yellow tinge to the skin, usually appearing first on the face and scalp, and then moving down the body to the chest, abdomen, arms, and legs. This yellowing of the skin is usually more noticeable on the head and face and can be harder to detect in dark-skinned babies.
• A yellow tinge to the white parts of the eyes (sclera).
• Yellow palms of the hands and soles of the feet (in severe cases).
• Feeding difficulties.
• Light-coloured faeces (poo) and dark urine.

Jaundice usually appears on the second or third day after birth and disappears by the time the baby is two weeks old. In premature babies, it can take five to seven days to appear and usually lasts about three weeks.

If you notice any of these symptoms in your newborn, it is important to consult a healthcare professional for advice. While jaundice is common and often harmless, in rare cases, very high levels of bilirubin can lead to severe jaundice and put the baby at risk of brain damage.

How is it diagnosed?

Jaundice is a common condition in newborns, affecting around 50% of full-term babies and up to 80% of premature babies. It is typically diagnosed by observing the yellowing of a baby's skin and eyes, which may start on the face and spread across the body. However, in some cases, jaundice can be challenging to detect, especially in babies with darker skin tones. To confirm the diagnosis, doctors will typically perform the following:

Physical Examination:

• Visual Inspection: The first step is to examine the baby's skin and eyes for any yellow discolouration. This is usually done by gently pressing the skin on the baby's nose or forehead. If jaundice is present, the skin will appear yellow when the finger is lifted.
• Bilirubin Levels: Doctors will measure the level of bilirubin in the baby's blood, as this indicates the severity of jaundice. This can be done through a blood test or a transcutaneous bilirubinometer, which measures the reflection of light through the skin.

Additional Tests:

• Blood Tests: If jaundice is suspected or confirmed, additional blood tests may be ordered to determine the underlying cause. These tests can include a complete blood count (CBC), blood type, and Rh incompatibility testing.
• Urine Tests: In some cases, urine tests may be necessary if there is evidence of an underlying disorder, such as sepsis, urinary tract infection, or galactosemia.
• Coombs Test: This test checks for antibodies that indicate an elevated risk of increased red blood cell breakdown (hemolysis).

Monitoring and Follow-up:

• Frequent Monitoring: Guidelines recommend that all newborn babies be examined for jaundice at least every 12 hours after birth and until their discharge from the hospital.
• Follow-up Visits: If risk factors for severe jaundice are present, such as prematurity or a family history of jaundice, doctors may recommend follow-up visits shortly after the baby leaves the hospital.

It is important to note that mild jaundice may resolve on its own within a few weeks as the baby's liver matures and feeding improves. However, more severe cases may require treatment, such as phototherapy or, in rare cases, exchange transfusion of blood.

How is it treated?

Jaundice in newborns is usually treated by addressing the underlying cause of the condition. The treatment depends on the cause of the jaundice, the bilirubin levels, and the baby's age. Here are some common treatments for jaundice in newborns:

• Frequent Feedings: For full-term, healthy babies, jaundice can often be resolved without any specific treatment other than frequent feedings. Breastfeeding jaundice, which occurs when a baby doesn't get enough breast milk, can be treated by increasing the frequency of feedings. This helps to lower the risk of jaundice and improve bilirubin levels. Breastfeeding mothers should aim for 8 to 12 feedings per day during the first week of life.
• Phototherapy: In more serious cases of jaundice, phototherapy may be used. This involves placing the baby under special blue lights with minimal clothing so that their skin is exposed. The light helps break down the bilirubin in the baby's skin, allowing it to be eliminated from the body. Phototherapy can be administered in a hospital setting or at home using "bili lights" or "bili-blankets" for mild cases.
• Blood Transfusion: In severe cases of jaundice, a blood transfusion or blood exchange may be necessary. This is done when very high bilirubin levels do not respond to phototherapy. The procedure involves replacing the baby's blood with blood from a donor to quickly lower bilirubin levels.
• Intravenous Immunoglobulin (IVIg): Babies with blood type incompatibilities may receive IVIg through an IV. This treatment blocks antibodies that attack red blood cells and reduces the need for an exchange transfusion.
• Supplementing with Formula: For newborns with breastfeeding jaundice, supplementing with formula may be recommended if the baby is not getting enough breast milk.
• Treating Underlying Conditions: In some cases, jaundice may be caused by underlying conditions such as internal bleeding, infections, or liver problems. Treating these underlying conditions is essential for managing jaundice.

It is important to monitor jaundice in newborns closely, as high bilirubin levels can lead to serious complications, including brain damage and cerebral palsy. Most cases of jaundice in newborns resolve within 1 to 2 weeks as the baby's liver matures and becomes more efficient at removing bilirubin from the body.

Frequently asked questions