Jaundice: common, meant to be measured before discharge, treated in about two in a hundred
Around 60% of term babies go yellow in the first week. In a current US hospital network, about 2 in 100 received light treatment.
Jaundice is the single commonest reason a newborn gets extra tests, extra days in hospital, or a trip back after discharge. Parents are told some babies go a bit yellow. They are rarely told it is most of them.
How many go yellow. The clearest official statement available is British, from the UK national guideline, and is labelled as British here because no equivalent US figure could be verified: Approximately 60% of term and 80% of preterm babies develop jaundice in the first week of life
, and about 10% of breastfed babies are still jaundiced at 1 month
. The same document says For most babies, jaundice is not an indication of an underlying disease, and this early jaundice (termed 'physiological jaundice') is usually harmless
.
How many get a diagnosis in a US hospital. In a national sample of US newborn hospital discharges, the proportion of term infants carrying a coded diagnosis of high bilirubin rose from 9.4% in 1997 to 15.5% in 2012. That is a coded diagnosis rate, not a measured-yellowness rate, and the two are not the same thing.
How many actually get treated. This number moves with policy, not just with babies, and that is the important part.
| Population | Received light treatment in hospital |
|---|---|
| The 38,182 babies (of 358,086 born at 35 weeks or later and 2,000 g or more, one California health system, 1995 to 2007) who were born at hospitals with universal bilirubin screening | 9.1% |
| The same system, hospitals without universal screening | 4.2% |
| More than 22,000 babies born at 35 weeks or later, 8 US hospitals, in the eight months before the 2022 guideline | 3.9% |
| The same 8 hospitals, after the 2022 guideline | 2.1% |
Those are four separate observations from two different eras and two different hospital systems. They are not a single trend line and should not be read as one. What they show together is that whether your baby gets light treatment depends heavily on which hospital you are in and which year it is.
The outcome everyone is actually afraid of. Kernicterus is the permanent brain injury that untreated severe jaundice can cause. In US hospital discharge data it fell from 7 per 100,000 newborns in 1997 to 1.9 per 100,000 in 2012. That is roughly 2 in every 100,000 babies. It is the reason your baby's bilirubin gets measured, and it is very rare.
About the 2022 guideline, and what this guide will not tell you. US practice follows the American Academy of Pediatrics 2022 clinical practice guideline. Its full text could not be opened for this guide, because the publisher refuses automated access. So no treatment threshold number, no comparison with the older 2004 thresholds and no follow-up interval is quoted here from inside that document. What can be verified from public summaries: the companion technical report states New evidence indicates that neurotoxicity does not occur until bilirubin concentrations are well above the 2004 exchange transfusion thresholds
, and the Academy's own patient page states that the guideline recommends that all newborns have their bilirubin level measured at least once prior to discharge
. If someone quotes you a specific number from that guideline, ask them to show you the figure it comes from.
One more link worth knowing: in the California readmission study, jaundice was the reason for 58.9% of readmissions in healthy late preterm babies, whose 30-day readmission rate was 5.9%.
"Is that going up, and how fast?"
"When does it need rechecking, and where?"
"What would I see at home that should bring us back the same day?"