In the first days after birth, some families notice that the baby’s skin is turning yellowish.
Sometimes the yellow shows up first on the face, and it can also be seen in the white part of the eyes.
This condition is called neonatal jaundice, popularly known in Brazil as “amarelão” (“the yellows”).
It is very common in newborns and is often part of the body’s adjustment after birth.
Even so, jaundice needs to be watched carefully, because very high bilirubin levels may require treatment.
What causes jaundice?
The yellowish color happens when there is a higher amount of bilirubin in the blood.
Bilirubin is a substance produced naturally as red blood cells are renewed.
Before birth, part of this processing happens with the help of the placenta.
Once the baby is born, the baby’s own body needs to take over this job.
Because a newborn’s liver is still maturing, it may not be able to clear bilirubin as efficiently as an older child’s or an adult’s.
The result can be a temporary buildup in the blood and the appearance of a yellowish color.
Is jaundice common in the first days?
Yes.
Jaundice is one of the most frequent findings in the newborn period.
The Brazilian Society of Pediatrics (SBP) reports that it appears in approximately 60% of full-term newborns and 80% of premature babies during the first week of life.
In what is called physiological jaundice, the color usually appears after the first 24 hours of life and gradually fades as the baby’s body matures.
In most full-term newborns, it tends to disappear within the first few weeks.
How can you spot jaundice?
The best-known sign is a yellowish color of the skin.
It may first appear:
on the face;
in the white part of the eyes;
on the chest.
As bilirubin levels rise, the color may spread to the belly, arms and legs.
But looking at skin color alone is not enough to know how much bilirubin is in the blood.
This is especially important because what we see can vary depending on the lighting and the baby’s skin tone.
When needed, professionals use devices that estimate bilirubin through the skin or order a blood test.
Jaundice in the first 24 hours needs attention
This is a very important point.
When jaundice appears before the baby is 24 hours old, it should not be considered simply physiological.
Brazil’s Ministry of Health recommends a thorough evaluation in these cases, as there may be another cause behind the rise in bilirubin.
So, if you notice a newborn turning yellow on the very first day of life, tell the maternity team immediately or seek medical care.
Why do some babies get more yellow?
There are different reasons why bilirubin can rise.
These may include:
liver immaturity;
prematurity;
feeding difficulties;
excessive weight loss;
blood type incompatibility between mother and baby;
increased breakdown of red blood cells;
bruising related to birth;
some infections;
genetic or metabolic conditions;
diseases of the liver or bile ducts.
It is precisely because there are different causes that not all jaundice should be treated the same way.
Is breastfeeding related to jaundice?
It can be, but that does not mean breast milk is bad for the baby.
In the first days, when the baby is not able to take in enough milk — because of latch or sucking difficulties or other situations — there may be greater weight loss and less bilirubin being cleared.
That is why, when there is jaundice, the team will usually also look at:
how the latch is going;
how often the baby feeds;
weight gain or loss;
amount of urine;
bowel movements.
Fixing breastfeeding difficulties can be part of the care.
Do not stop breastfeeding or give water, tea or other drinks on your own to try to “flush out the yellow.”
When any change in feeding is needed, it should be guided by the team caring for the baby.
Does the baby need a test?
Not every slightly yellow baby necessarily needs a blood draw.
The evaluation depends on the baby’s age in hours, how intense the jaundice is, the baby’s history and the presence of risk factors.
Bilirubin can be estimated with a device placed on the skin, called a transcutaneous bilirubinometer.
When needed, bilirubin is measured in the blood.
The team interprets the result mainly in light of how many hours or days old the baby is, because the same value can mean different things at different times.
When is treatment needed?
Many cases improve naturally as the body matures.
When bilirubin reaches levels that require treatment, one of the main options is phototherapy.
In this treatment, the baby is exposed to a specific light that helps the body transform bilirubin so it can be eliminated more easily.
How long phototherapy lasts depends on how bilirubin levels evolve and on the baby’s characteristics.
In rare and severe situations, other treatments may be needed.
Does putting the baby in the sun treat jaundice?
Do not use sun exposure as a substitute for the evaluation and treatment recommended by professionals.
Hospital phototherapy is not simply “sunbathing.”
It uses light with controlled characteristics and intensity and is carried out while monitoring bilirubin levels.
Besides making it impossible to control the dose of light received, leaving a newborn directly in the sun can cause burns and changes in body temperature.
If the baby is yellow, talk to the health team instead of trying to treat it at home with sun exposure.
When can jaundice be dangerous?
When the amount of indirect bilirubin gets very high, it can cross certain barriers in the body and reach the brain.
This complication is rare, but it can cause bilirubin encephalopathy and, in the most severe cases, permanent damage.
That is why monitoring jaundice and treating it when indicated is important even when the baby seems well.
When should you seek care quickly?
Seek medical evaluation if:
the jaundice appeared in the first 24 hours of life;
the baby is getting progressively more yellow;
the color reaches the legs, hands or feet;
the baby is having trouble feeding;
the baby is very sleepy and hard to wake for feeds;
the baby is behaving very differently than usual;
the baby has a fever or other signs of illness;
the baby seems to be losing a lot of weight;
the family is worried about how things are going.
It is also important to go back for the visits and checkups recommended after discharge from the maternity hospital.
Watch out for very pale stools
The color of the stools can also provide important information.
Babies with persistent jaundice along with very pale, whitish or grayish stools need to be evaluated quickly.
Likewise, very dark urine that stains the diaper deserves attention.
These signs may be related to problems with the flow of bile, such as biliary atresia, a condition that needs early diagnosis.
What if the baby is still yellow after two weeks?
Jaundice that lasts longer deserves evaluation.
The Brazilian Society of Pediatrics advises investigating babies who are still jaundiced after the first 14 days, mainly to tell benign forms apart from problems of the liver or bile ducts.
This does not mean that all prolonged jaundice is serious.
Breastfed babies may stay yellowish for longer.
Even so, the pediatrician needs to assess the case and decide whether tests are needed.
Watch the baby, not just the skin color
When there is jaundice, it is also worth observing how the baby is doing day to day.
Pay attention to whether the baby:
wakes up to feed;
is able to feed well;
pees and poops;
seems alert when awake;
is gaining or regaining weight;
shows any significant change in behavior.
This information helps the professional assess the situation as a whole.
The “yellows” are common, but need follow-up
Seeing a newborn turn a little yellow can be scary, especially in the first days at home.
In most cases, neonatal jaundice is related to the body’s natural adjustment and improves as the baby grows.
But it is not possible to determine how serious it is just by looking at how intense the color is.
That is why evaluations at the maternity hospital, follow-up in the first days and return visits to the pediatrician are important to make sure bilirubin levels stay safe.
Nilu tip: if you notice the baby turning yellow, also pay attention to how they are feeding, waking up, peeing and pooping. This information can be a big help during the evaluation with the pediatrician. 💛
Reference sources
Brazil’s Ministry of Health — Jaundice in the newborn (neonatal jaundice).
Brazil’s Ministry of Health — Newborn Health Care.
Brazilian Society of Pediatrics — Indirect hyperbilirubinemia in the neonatal period.
Brazilian Society of Pediatrics — Biliary atresia.
This content is for educational and informational purposes and does not replace consultations, evaluations, diagnosis or individualized guidance from health professionals. Newborns with jaundice should be evaluated as advised by the health team.