A Simpler Newborn Heart Check: What the 2025 Update to Pulse Oximetry Screening Means for Your Baby

Understanding the 2025 American Academy of Pediatrics report on screening newborns for serious heart conditions, and the research behind it

Why newborns are screened for heart problems

Some babies are born with serious heart conditions known as critical congenital heart disease, or CCHD — heart defects that can become life-threatening in the first months of life unless they are found and treated early. Many of these conditions lower the amount of oxygen in a baby's blood, often before the baby looks unwell. To catch this, hospitals use a quick, painless test called pulse oximetry: a small sensor is placed on the baby's right hand and on a foot to estimate how much oxygen is in the blood. The idea of using this simple bedside test to screen all newborns was supported by a major expert review in 2009 [1] and by large real-world studies, including one in Sweden that screened 39,821 babies [2]. In 2011 it became a recommended part of newborn care in the United States, and by 2018 every US state and territory was doing it [3]. Before this kind of screening became routine, some babies with serious heart conditions were sent home looking healthy, only to become critically unwell in the first days or weeks of life when the problem finally revealed itself. Catching these conditions before a baby leaves hospital — when help is immediately at hand — was the central reason the screen was developed and then recommended for every newborn.

How the test works

The reason the sensor goes on both a hand and a foot is that the two locations tell doctors slightly different things. The right hand receives blood from the heart before it reaches a connection called the ductus arteriosus, while the foot receives blood from after that point. Comparing the two can reveal certain heart problems that affect one part of the circulation more than the other. The whole check takes only a few minutes, causes the baby no pain, and is usually done when the baby is at least 24 hours old, before going home. A nurse simply reads the oxygen levels from the two sensors and compares them against the passing rule.

What the 2025 update says

In January 2025, the American Academy of Pediatrics (AAP) — the main professional body for children's doctors in the US — published a report that updates how this screening should be done [3]. The biggest change is that the test has been made simpler, using an approach first proposed by an expert panel in 2020 [4]. There are two practical differences from the old version.

First, to pass, a baby now needs an oxygen reading of at least 95% in both the hand and the foot. Under the old rules, a baby could pass with a good reading in either the hand or the foot. Requiring both is clearer and leaves less room for confusion [5]. Second, if the first result is in-between — not a clear pass and not a clear fail — the baby is now retested only once instead of twice. Research that modelled different approaches found that dropping the extra retest barely changes how often the test gives a false alarm, while getting babies who truly need help to the next step faster [6].

A small but important detail: room air

The report also clarifies that the test should be done while the baby is breathing ordinary room air, not while receiving extra oxygen [3]. The reason is straightforward: extra oxygen can push the reading up and make a baby look fine when there is actually a problem to find. So if a baby has needed some breathing support, the team will usually wait until the baby is breathing room air before screening — even if that means screening a little later than usual. This is one reason a screen is sometimes delayed in babies who spent time in intensive care, and it is nothing for parents to worry about — it simply ensures the result is accurate.

What the test can and cannot do

It is important for families to understand both the strengths and the limits of this screen. Pulse oximetry is very good at picking up heart problems that lower oxygen, but it cannot catch every kind of heart defect. Across all the conditions it targets, it finds somewhere between roughly half and three-quarters of cases; for one particular defect, called coarctation of the aorta, it may catch as few as one in five [7]. In plain terms: passing the screen is reassuring, but it does not completely rule out a heart problem. That is why the screen never replaces a doctor's examination, and why parents should always seek advice if their baby feeds poorly, breathes fast or with effort, or changes colour.

There is a useful flip side. Sometimes a baby does not pass the screen but turns out not to have a heart problem at all. This is not a failure of the test. A low oxygen reading can be an early sign of other treatable conditions, such as an infection or a lung problem [5]. Finding these early can help a baby get care sooner, so a "failed" screen that leads to a different diagnosis can still be a good outcome.

What happens if your baby does not pass

If a baby does not pass, it does not mean something is definitely wrong with the heart. It means the care team will take a closer look, usually quite quickly. This typically involves repeating the oxygen check, a careful physical examination, and often an ultrasound scan of the heart called an echocardiogram, which is also painless. The team will look for a heart cause and, just as importantly, for other treatable explanations such as an infection or a breathing problem. Most babies who do not pass the screen turn out either to have one of these other conditions or to be perfectly healthy. Knowing this in advance can make the experience far less frightening if it happens to your family. If your hospital does not have a heart specialist on site, the team may use a video link to a specialist elsewhere or arrange a transfer, so that the next steps happen without delay.

Does the screening actually help? The evidence

Families can be reassured that this screening is not just a precaution on paper — it has been shown to save lives. After US states began requiring CCHD screening, the number of early infant deaths from these heart conditions dropped by about a third [8]. States with screening rules also saw fewer emergency hospital admissions for these conditions [9]. The test is also inexpensive and quick, and adopting it did not lead to a flood of unnecessary extra tests as some had feared [10]. The 2025 update keeps all of these benefits while making the test simpler to perform [4].

What researchers are working on next

The report is honest about where screening can still improve, and these are the areas researchers are now focused on. One priority is finding the heart defects that pulse oximetry tends to miss, such as coarctation of the aorta, perhaps by combining oximetry with other measurements or new technology — though early attempts to add extra measures caused too many false alarms to be useful yet [3]. A second priority is fairness. There is concern that pulse oximetry readings may be less accurate depending on a baby's skin tone, and researchers are studying this closely to make sure the test works equally well for every baby [11]. Because not all heart conditions are picked up before birth, and prenatal detection is less likely for families with fewer resources, the newborn screen acts as an important safety net — and making that safety net work equally for everyone is a clear goal [3].

Better record-keeping behind the scenes

Two of the report's recommendations are aimed at hospitals and health departments rather than at families directly, but they still matter for your baby's care. The report asks states to collect the same core information about every screen and to connect that information with other health records, so that any missed cases can be found and the programme can keep improving [3]. It also encourages hospitals to build the screening steps into their electronic record systems. In one hospital that did this, almost every baby — 98.9% — was screened before going home, because the computer system prompted staff automatically and reduced the chance of a baby slipping through [12]. For parents, the takeaway is simple: behind a quick test on your newborn's hand and foot sits a carefully studied, continually improving system designed to give every baby the best chance of a healthy start. The 2025 update is a good example of that system at work — a decade of real-world experience used to make the test simpler and clearer without giving up any of its life-saving value.

References

  1. Mahle WT, Newburger JW, Matherne GP, et al. Role of Pulse Oximetry in Examining Newborns for Congenital Heart Disease: A Scientific Statement from the AHA and AAP. Pediatrics. 2009;124(2):823-836. doi:10.1542/peds.2009-1397 ↩
  2. de-Wahl Granelli A, Wennergren M, Sandberg K, et al. Impact of Pulse Oximetry Screening on the Detection of Duct Dependent Congenital Heart Disease: A Swedish Prospective Screening Study in 39,821 Newborns. BMJ. 2009;338:a3037. doi:10.1136/bmj.a3037 ↩
  3. Oster ME, Pinto NM, Pramanik AK, et al. Newborn Screening for Critical Congenital Heart Disease: A New Algorithm and Other Updated Recommendations: Clinical Report. Pediatrics. 2025;155(1):e2024069667. doi:10.1542/peds.2024-069667 ↩
  4. Martin GR, Ewer AK, Gaviglio A, et al. Updated Strategies for Pulse Oximetry Screening for Critical Congenital Heart Disease. Pediatrics. 2020;146(1):e20191650. doi:10.1542/peds.2019-1650 ↩
  5. Oster ME, Aucott SW, Glidewell J, et al. Lessons Learned from Newborn Screening for Critical Congenital Heart Defects. Pediatrics. 2016;137(5):e20154573. doi:10.1542/peds.2015-4573 ↩
  6. Diller CL, Kelleman MS, Kupke KG, Quary SC, Kochilas LK, Oster ME. A Modified Algorithm for Critical Congenital Heart Disease Screening Using Pulse Oximetry. Pediatrics. 2018;141(5):e20174065. doi:10.1542/peds.2017-4065 ↩
  7. Ailes EC, Gilboa SM, Honein MA, Oster ME. Estimated Number of Infants Detected and Missed by Critical Congenital Heart Defect Screening. Pediatrics. 2015;135(6):1000-1008. doi:10.1542/peds.2014-3662 ↩
  8. Abouk R, Grosse SD, Ailes EC, Oster ME. Association of US State Implementation of Newborn Screening Policies for Critical Congenital Heart Disease With Early Infant Cardiac Deaths. JAMA. 2017;318(21):2111-2118. doi:10.1001/jama.2017.17627 ↩
  9. Sakai-Bizmark R, Kumamaru H, Marr EH, et al. Pulse Oximetry Screening: Association of State Mandates with Emergency Hospitalizations. Pediatr Cardiol. 2023;44(1):67-74. doi:10.1007/s00246-022-03027-3 ↩
  10. Peterson C, Grosse SD, Oster ME, Olney RS, Cassell CH. Cost-Effectiveness of Routine Screening for Critical Congenital Heart Disease in US Newborns. Pediatrics. 2013;132(3):e595-e603. doi:10.1542/peds.2013-0332 ↩
  11. Ruppel H, Makeneni S, Faerber JA, et al. Evaluating the Accuracy of Pulse Oximetry in Children According to Race. JAMA Pediatr. 2023;177(5):540-543. doi:10.1001/jamapediatrics.2023.0071 ↩
  12. Zarouni SA, Mheiri NMA, Blooshi KA, et al. Impact of an Electronic Medical Record-Based Automated Screening Program for Critical Congenital Heart Disease. BMC Med Inform Decis Mak. 2022;22(1):165. doi:10.1186/s12911-022-01900-y ↩