Neonatal Jaundice: What UK Parents Need to Know

5 min read

Quick answer: Neonatal jaundice is a yellowing of the skin and eyes caused by a build-up of bilirubin, and it affects around 6 in 10 UK newborns. It is usually most noticeable when a baby is around 3 days old and usually takes around 2 weeks to go. Frequent feeding helps; moderate or severe cases are treated with phototherapy in hospital.

What parents need to know

Leaving hospital with a jaundiced baby — or being asked to stay in a little longer because of it — can feel worrying. But neonatal jaundice is extremely common, affecting around 6 in 10 newborns in the UK, and in most cases it is mild and resolves on its own within a couple of weeks.

What is neonatal jaundice?

Jaundice is a yellowing of the skin and whites of the eyes caused by a build-up of bilirubin in the blood. Bilirubin is a yellow substance produced when red blood cells break down. Newborns have higher levels of red blood cells than adults, and their immature livers are not yet efficient at processing bilirubin quickly enough — causing it to accumulate temporarily.

What does jaundice look like?

The yellowing typically appears first on the face and spreads downward to the chest, tummy, arms and legs as bilirubin levels rise. It's easiest to see in natural daylight. The whites of the eyes may also appear yellow.

For most babies, the yellow is most noticeable when they are around 3 days old, and it usually takes around 2 weeks to go. In some well, breastfed babies it lasts longer (breastmilk jaundice), but prolonged jaundice can also have other causes, such as infection, thyroid problems or, rarely, liver disease. Speak to your GP if jaundice lasts longer than 2 weeks (3 weeks if your baby was born premature).

Types of neonatal jaundice

Physiological jaundice: The most common type, appearing after 24 hours and caused by normal newborn physiology. Usually mild and self-resolving.
Breastmilk jaundice: Jaundice that carries on for longer in some well, breastfed babies. It is not a reason to stop breastfeeding, but jaundice lasting longer than 2 weeks (3 weeks if your baby was born premature) should be checked by your GP, as it can have other causes.
Pathological jaundice: Less common. Appears within the first 24 hours of life or is more severe. Can be caused by blood group incompatibility, infection, or other conditions. Requires prompt medical assessment. If your baby is less than 24 hours old and has jaundice, call 999 or go to A&E.

How is jaundice treated?

Mild jaundice usually needs no treatment beyond monitoring, keeping your baby well-fed, and ensuring regular nappy output.

Moderate to severe jaundice is treated with phototherapy — placing your baby under a special blue light (or on a light blanket) that helps break down bilirubin in the skin. Phototherapy is safe and effective and is usually carried out in hospital, although sometimes you may be given equipment to use at home. In very rare cases where bilirubin levels are very high, an exchange transfusion may be needed.

The importance of feeding

Frequent feeding is one of the most important things you can do to help jaundice resolve. Feeding — whether breast or formula — helps the body excrete bilirubin through stools, which is why well-fed babies tend to have milder and shorter jaundice. Aim to feed at least 8–12 times in 24 hours in the newborn period.

When to get help

Call 999 or go to A&E if your baby has jaundice and:

Is less than 24 hours old
Is sleepier than normal or difficult to wake
Is not feeding
Is floppy or stiff, or has jerking or twitching movements
Has a high temperature of 38°C or more, or a low temperature of 36°C or less, feels hot or cold to the touch, or is shivering
Has not been producing any wet nappies
Has difficulty breathing (you may notice grunting noises or their tummy sucking in under their ribcage), is breathless or is breathing very fast

Do not drive to A&E. Ask someone to drive you, or call 999 and ask for an ambulance.

Ask for an urgent GP or midwife appointment, or call NHS 111, if your baby is over 24 hours old and:

You think they have jaundice
They have been diagnosed with jaundice and it is not getting better, or is getting worse
Their pee is dark yellow or brown, or their poo is a pale creamy colour (keep a sample of poo to show a midwife or doctor)
Their jaundice has lasted more than 2 weeks (or more than 3 weeks if they were born before 37 weeks)

Call 999 or go to A&E immediately if your baby has a very high-pitched or unusual cry, arched back, or is unusually floppy.

Frequently asked questions

How common is jaundice in newborn babies?

It's common, affecting around 6 in 10 newborns in the UK. In most cases it's mild and resolves on its own within a couple of weeks.

When does newborn jaundice usually appear and go away?

It's usually most noticeable when a baby is around 3 days old and usually takes around 2 weeks to go. If it lasts longer than 2 weeks (3 weeks if your baby was born premature), speak to your GP, even if your baby is breastfed and seems well.

Should I stop breastfeeding if my baby has jaundice?

No. There is no need to stop breastfeeding if your baby has jaundice. Some well, breastfed babies do have jaundice for longer, but if it lasts longer than 2 weeks (3 weeks if your baby was born premature), ask your GP to check your baby, as prolonged jaundice can have other causes.

How often should I feed a jaundiced newborn?

Aim to feed at least 8–12 times in 24 hours in the newborn period. Feeding, whether breast or formula, helps the body excrete bilirubin through stools.

Sources & further reading

General information, not individual medical advice. Speak to your GP, midwife or health visitor about your baby’s needs.