Bradycardia in Newborns:
Understanding, Supporting, and Thriving Beyond the NICU
What is Bradycardia?
- Bradycardia means a slower-than-normal heart rate — often below 100 beats per minute in infants.
- Brief episodes are common in preemies or medically fragile infants and usually reflect an immature nervous system rather than heart disease.
- Bradycardia may occur when liquid gets too close to the airway and triggers a response that was originally meant for the developing fetus.
- The second main reason is when an infant is pushed past their limits and loses physiologic stability.
- Other causes include prematurity, apnea, feeding difficulties, and other medical factors.
- Most babies outgrow bradycardia as they mature, but ongoing monitoring and follow-up care are important.
- Infant Feeding Specialists are trained to help manage these events and support your baby’s feeding and development
- Parents are not alone — guidance, monitoring, and therapy help families feel confident and supported after the NICU.
Fetal Protective Reflex
Bradycardia is a term you may have heard in the NICU or from your baby’s care team. It refers to a slower-than-normal heart rate — typically below 100 beats per minute in newborns. Seeing your baby’s heart slow can feel frightening, but for many preemies and medically fragile infants, brief episodes are common and often a normal part of early development.
At Infant Feeding Specialists, we help families navigate life after the NICU, supporting feeding, growth, and overall development. We look beyond the numbers to help your baby thrive.
Why Bradycardia Happens in Newborns
Bradycardia can occur for several reasons, especially in preterm or medically complex babies. There are a few common theories:
What Is Bradycardia in Newborns?
Brief episodes are usually linked to an immature nervous system rather than heart disease. While persistent or severe bradycardia needs medical attention, most infants gradually outgrow these episodes as their systems mature.
- Parent Note: Leaving the NICU can feel overwhelming. Even if your baby is medically stable, you might still worry when you see a pause in breathing or a monitor alarm at home. That’s completely normal — and support is available.
The most common theory relates to the persistence of a Fetal Protective Reflex.
In the womb the infant is surrounded by amniotic fluid. While the amniotic fluid is great for many reasons, the fluid itself is full of debris, like skin cells, hair and other substances. This debris can be very damaging to the fetus’ developing lungs, which should only be exposed to Fetal Lung Fluid. To ensure the fetus does not accidentally get any of the amniotic fluid into their developing lungs, the fetus has a “Fetal Protective Reflex” which temporarily shuts down the practice breathing movements. This is safe for the fetus because they are receiving all of their oxygenation through the umbilical cord. This reflex is triggered anytime a fluid goes near the upper airway that does not match the chemical composition of their fetal lung fluid. This reflex naturally goes away by the time the infant is born at 40 weeks and it will transition into the “Laryngeal Chemo Reflex” which instead triggers a cough or startle response.
But for infants born preterm, this reflex continues to trigger bradycardia, laryngospasm (closing of the vocal folds) and/or apnea (cessation of breathing) — mimicking what it would have done in the womb. Preemies have a difficult time coordinating sucking, swallowing and breathing. This incoordination results in some liquid being directed towards the airway instead of the stomach. The presence of that liquid in the upper airway is often responsible for triggering that “protective” reflex, resulting in bradycardias, desaturations or apneas (aka cardiorespiratory events) at bedside. Reflux of material from the stomach or nasal cavity can also trigger these responses.
Physiologic Instability
The second most common theory for Bradycardia involves the infant’s physiologic stability.
A famous clinical researcher came up with the Synactive Theory of Development (Als, 1982). She created a framework to understand the behaviors of infants, and explained that when infants are challenged by their environment they lose stability in 5 subsystems. The last subsystem to decompensate is the autonomic subsystem, which controls heart rate.
This is relevant to feedings in that if we exhaust infants when they learn how to feed, and we continually ignore their behavioral cues of physiologic instability, we can eventually work them so hard they have a bradycardia. It is therefore important that caregivers take appropriate measures to feed these infants appropriately, using a cue-based, co-regulated approach.
Other Reasons
Apnea of prematurity: Short pauses in breathing can lead to heart rate drops.
Other medical factors: Low oxygen levels, infections, low blood sugar, or heart rhythm issues.
These causes are often closely monitored in the NICU. As babies grow, their nervous systems mature, and bradycardia episodes typically improve.
Recognizing and Monitoring Bradycardia After the NICU
- Brief color changes to pale, white or bluish, especially around their lips and face
- A long pause in breathing
- A frozen, shocked look on their infants face
- Their infant turning limp
When these events occur without a monitor in place, the technical term is a “BRUE” (bru-ee) = Brief, Resolved, Unexplained, Event.
- Reassurance: Most babies outgrow bradycardia episodes as they mature and as they better learn how to coordinate their movements for feedings. Ongoing follow-up with your pediatrician or specialists helps ensure your baby’s heart and breathing are developing normally. Most episodes are short and resolve on their own, but some may need gentle stimulation or medical support.
Feel More Confident at Every Feeding
If your baby has experienced bradycardia or feeding challenges, our specialists can help you navigate the next steps with confidence.
FAQs About Bradycardia in Newborns
What is a normal heart rate for a newborn?
A typical newborn heart rate is 120–160 beats per minute. Bradycardia occurs when it drops below about 100 beats per minute.
Is bradycardia dangerous for babies?
Not always. Many preemies experience mild, temporary bradycardia that resolves as they mature. Persistent or severe episodes should be evaluated by a doctor.
Will my baby outgrow bradycardia?
Most infants do outgrow these events as their nervous systems mature. Continued monitoring and supportive care help ensure healthy development.
Can therapy help if my baby had bradycardia in the NICU?
Yes. Infant Feeding Specialists can assess the relationship between your infant's feeding skills and bradycardia events to develop a personalized plan for safe, confident progress.
What if my baby still struggles to feed after discharge?
This is common. Our feeding specialists help identify underlying factors and build a plan that supports your baby’s unique needs.
How Feeding Therapy Supports infants with Bradycardia during Feedings
- Teaching safe and efficient feeding strategies such as the pacing technique or different feeding positions.
- Switching to appropriate feeding devices, such as bottles and nipple flow rates, to improve suck, swallow, breathe coordination to reduce liquid misdirection towards the airway.
- Gradually building endurance without triggering physiologic instability in the autonomic subsystem.
- Teaching parents how to respond when their infant has an event at bedside
Tips for Parents:
- Feeding should always be guided by professionals if bradycardia has been present.
- Safe and supportive strategies can make feeding more appropriate and help your baby grow.
- Frequent or severe episodes may be linked to longer hospital stays or, rarely, to risks for developmental delays, especially if they happen with low oxygen.
How Infant Feeding Specialists Helps Babies with Bradycardia Thrive
Our services include:
- Infant Feeding Evaluations: Identify whether feeding difficulties are related to bradycardia or other factors, and receive a customized feeding plan.
- If you baby is still in the NICU and you want to seek advice about frequent bradycardias, schedule a NICU Care Consult to speak to a specialist
- Individualized, Customized Feeding Plans: Focus on safety, endurance, and positive experiences.
- Ongoing Developmental Support: Support motor skills, growth, and parent-baby connection.
“Your baby’s heart has found its rhythm — now let’s help their feeding and development do the same.”
References:
- Lasa, J. J., Dhillon, G. S., Duff, J. P., et al. (2025). Part 8: Pediatric advanced life support: 2025 American Heart Association and American Academy of Pediatrics guidelines for cardiopulmonary resuscitation and emergency cardiovascular care. Circulation, 152(16suppl2), S479–S537. https://doi.org/10.1161/CIR.0000000000001368
- Chaudhry-Waterman, N., Nashed, L., Chidester, R., et al. (2023). A prospective evaluation of arrhythmias in a large tertiary neonatal intensive care unit. Pediatric Cardiology, 44(6), 1319–1326. https://doi.org/10.1007/s00246-022-03046-0
- Sidhu, S., & Marine, J. E. (2020). Evaluating and managing bradycardia. Trends in Cardiovascular Medicine, 30(5), 265–272. https://doi.org/10.1016/j.tcm.2019.07.001
- Veerappan, S., Rosen, H., Craelius, W., et al. (2000). Spectral analysis of heart rate variability in premature infants with feeding bradycardia. Pediatric Research, 47(5), 659–662. https://doi.org/10.1203/00006450-200005000-00017
- Sandau, K. E., Funk, M., Auerbach, A., et al. (2017). Update to practice standards for electrocardiographic monitoring in hospital settings: A scientific statement from the American Heart Association. Circulation, 136(19), e273–e344. https://doi.org/10.1161/CIR.0000000000000527
- Uusitalo, A., Tikkakoski, A., Reinikainen, M., et al. (2022). Extrasystoles or short bradycardias of the newborn seldom require subsequent 24-hour electrocardiographic monitoring. Acta Paediatrica, 111(5), 979–984. https://doi.org/10.1111/apa.16259
- Doyen, M., Hernández, A. I., Flamant, C., et al. (2021). Early bradycardia detection and therapeutic interventions in preterm infant monitoring. Scientific Reports, 11(1), 10486. https://doi.org/10.1038/s41598-021-89468-x
- Slocum, C., Arko, M., Di Fiore, J., Martin, R. J., & Hibbs, A. M. (2009). Apnea, bradycardia and desaturation in preterm infants before and after feeding. Journal of Perinatology, 29(3), 209–212. https://doi.org/10.1038/jp.2008.226
- Epstein, A. E., DiMarco, J. P., Ellenbogen, K. A., et al. (2013). 2012 ACCF/AHA/HRS focused update incorporated into the ACCF/AHA/HRS 2008 guidelines for device-based therapy of cardiac rhythm abnormalities: A report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines and the Heart Rhythm Society. Journal of the American College of Cardiology, 61(3), e6–e75. https://doi.org/10.1016/j.jacc.2012.11.007
Disclosure: The information on this page is for educational purposes only and is not medical advice, diagnosis, or treatment. It should not replace consultation with a qualified healthcare professional. Always seek the guidance of your physician or other licensed provider with any questions about a medical condition. If you think you may be experiencing a medical emergency, call your local emergency number immediately.