Periodic breathing is a repeating cycle in which a newborn breathes for several seconds, pauses briefly, and then breathes again, over and over in a rhythmic pattern. Each pause typically lasts a few seconds, far shorter than the prolonged pauses that define clinical apnea, and the cycles repeat roughly every ten to forty seconds. It looks alarming the first time you notice it, but it is one of the most common breathing patterns in newborns, especially premature ones. The story gets more interesting when you ask why it happens, when it crosses the line into something concerning, and what role it plays as the infant brain learns to regulate breathing on its own.
How the Pattern Looks and Is Defined
Clinicians generally define a periodic breathing episode as three or more short breathing pauses in a row, each lasting at least three seconds, separated by intervals of normal breathing that often last ten to fifteen seconds.1PubMed Central. Comparison of the longitudinal effects of persistent periodic breathing and apnoea on cerebral oxygenation in term- and preterm-born infants If you watch a baby’s chest closely during one of these episodes, you see short bursts of breaths followed by a still pause, then another burst, in a wave-like rhythm. Researchers who have quantified the pattern describe it as repetitive cycles of apnea and breathing occurring on a ten-to-forty-second timescale.2Physiological Measurement. Quantification of periodic breathing in premature infants
The shape of the breathing bursts changes with age. In premature infants, the pattern tends to be crescendo-decrescendo: breaths start shallow, build to deeper ones, then taper off before the next pause. In adults who experience periodic breathing (as in Cheyne-Stokes respiration during heart failure or at high altitude), the pattern shifts to a predominantly decrescendo shape, with deeper breaths arriving at the start of each burst and tapering from there. The total cycle length roughly doubles from infancy to adulthood, but the number of breaths packed into each burst stays about the same.3PubMed. The morphology of periodic breathing in infants and adults This difference hints that the newborn respiratory system is using a fundamentally different control strategy than the adult one, shaped by the mechanical and neural limitations of early life.
How Common It Is
Very common. In one well-known study, about 78% of full-term newborns showed periodic breathing at some point during their first two weeks of life.4PubMed. Apnea and periodic breathing in normal full-term infants during the first twelve months In premature and low-birth-weight infants, the numbers are even higher. Research has found periodic breathing in roughly 36% of infants weighing over 2,500 grams at birth, compared to about 95% of infants with low birth weight.5Pediatric Research. Periodic Breathing in Premature and Neonatal Babies: Incidence, Breathing Pattern, Respiratory Gas Tensions, Response to Changes in the Composition of Ambient Air The takeaway: if your newborn breathes in this stop-and-start rhythm during sleep, the odds are strong that most babies in the next bassinet over are doing the same thing.
Why Newborns Breathe This Way
The root cause is an immature system for sensing and responding to carbon dioxide and oxygen. Adults have a finely tuned feedback loop: when carbon dioxide rises slightly, the brain smoothly increases breathing to compensate. In newborns, that loop overshoots. The brain detects rising carbon dioxide and ramps up breathing aggressively, which blows off too much carbon dioxide, which then drops below a critical threshold called the apneic threshold. Below that threshold, the drive to breathe temporarily shuts off, producing a pause. Carbon dioxide climbs again during the pause, crosses the threshold, and the cycle starts over.
Researchers quantify how “overreactive” this feedback loop is with a metric called loop gain. A higher loop gain means the system corrects too hard in both directions, making periodic breathing more likely. In preterm infants, studies comparing breathing patterns found that babies with periodic breathing had measurably higher loop gain than those without it. A loop gain above a specific threshold measured between 32 and 36 weeks predicted with good accuracy which infants would still have periodic breathing at six months.6Pediatric Research. Ventilatory control stability as a predictor of persistent periodic breathing in preterm infants Modeling work has confirmed that the interplay between the apneic threshold, chemoreceptor sensitivity, lung volume, and the time it takes blood to travel from the lungs to the brain’s sensors all contribute to the oscillation.7PubMed Central. Infant periodic breathing and apneic threshold
At the start of each breathing burst, carbon dioxide in the lungs is at its highest and oxygen is at its lowest. By the end of the burst, those values have flipped. This matches what you would expect if the system is oscillating around a set point it hasn’t yet learned to hold steady.3PubMed. The morphology of periodic breathing in infants and adults Think of it like a thermostat that swings the room from too hot to too cold and back because it cranks the furnace too high and then shuts it off completely, instead of making gentle adjustments.
Sleep State Matters
Periodic breathing is not evenly distributed across all sleep. The swings in ventilation are larger during active (REM) sleep than during quiet (non-REM) sleep.8PubMed Central. Analysis of periodic changes in ventilation in new-born infants Newborns spend a much larger fraction of their sleep in REM than adults do, which partly explains why periodic breathing is so prevalent in the first weeks of life. As the balance shifts toward more quiet sleep over the first year, one of the conditions that amplifies periodic breathing naturally recedes.
Interestingly, this connection between sleep states and breathing cycles in infants was first documented much earlier than most people realize. A 1926 Russian study recorded continuous respiration data along with eye and body movements during infant sleep and identified cyclical periods of increased breathing activity aligned with what we now call REM sleep. The complete sleep cycle length they estimated, about 50 minutes, is consistent with modern measurements.9Sleep. English translation of the first study reporting cyclical periods of increased respiration and eye and body motility during sleep in infants in 1926, with commentary The observation that breathing instability tracks active sleep has been consistent across nearly a century of research.
When It Fades and When It Doesn’t
Most full-term infants gradually outgrow periodic breathing. The proportion of infants exhibiting the pattern drops from roughly 78% in the first two weeks to about 29% by the end of the first year. However, among those who still do it, the fraction of sleep time spent in periodic breathing stays about the same, suggesting that what changes is whether a baby’s system produces the pattern at all, not how prominent the pattern is once triggered.4PubMed. Apnea and periodic breathing in normal full-term infants during the first twelve months
For preterm infants, the timeline is less predictable. The loop gain data mentioned earlier show that some premature babies retain an overreactive breathing control system well past their due date. Higher loop gain measured around 32 to 36 weeks was associated with periodic breathing still being present at six months of corrected age.6Pediatric Research. Ventilatory control stability as a predictor of persistent periodic breathing in preterm infants This does not mean something is necessarily wrong, but it does mean that premature infants deserve closer attention for longer.
What Happens to Oxygen Levels During Episodes
In many cases, the brief pauses in periodic breathing cause little or no meaningful drop in blood oxygen. But that is not always the case, particularly in preterm infants. One study found that during periodic breathing, about a quarter of the pauses were followed by a drop in oxygen saturation, compared to only about 6% of pauses during regular breathing. The speed of the desaturation was also roughly twice as fast during periodic breathing.10Early Human Development. Patterns of oxygenation during periodic breathing in preterm infants When desaturations did lead to heart rate drops below 100 beats per minute, virtually every one of those episodes was accompanied by oxygen saturation falling below 80%.
Supplemental oxygen can dramatically reduce periodic breathing. In late-preterm infants studied during sleep, the percentage of time spent in periodic breathing dropped from about 10% on room air to about 1% when supplemental oxygen was given. Central apnea events fell by roughly half, and oxygen desaturations dropped substantially as well.11PubMed Central. Supplemental Oxygen Treats Periodic Breathing without Effects on Sleep in Late-Preterm Infants This makes physiological sense: a little extra oxygen raises the baseline further from the apneic threshold, so the feedback loop doesn’t overshoot as far. In practice, supplemental oxygen is not routinely prescribed for otherwise healthy infants with periodic breathing, but the finding confirms that oxygen availability is central to the mechanism.
Environmental Triggers
Two environmental factors reliably influence periodic breathing: altitude and temperature.
At higher altitudes, the lower oxygen concentration in the air pushes the infant’s baseline oxygen saturation closer to the apneic threshold, making oscillation more likely. A systematic review of children living at high altitude in the Andes found that periodic breathing appeared only in the first four months of life and increased with increasing altitude.12PubMed Central. Breathing Patterns and Oxygenation Saturation During Sleep in Children Habitually Living at High Altitude in the Andes: A Systematic Review This matters for families who live in mountain communities or travel to high altitude with a young infant: expect more periodic breathing, and know that it does not by itself indicate a problem beyond the normal physiological stress of thinner air.
Heat is the other trigger. In premature infants, higher environmental temperatures near the upper end of the thermoneutral zone were associated with more apneic episodes.13Pediatrics. APNEA IN PREMATURE INFANTS: MONITORING, INCIDENCE, HEART RATE CHANGES, AND AN EFFECT OF ENVIRONMENTAL TEMPERATURE A study comparing both lambs and human newborns under moderate heat stress found that both developed rapid breathing interspersed with short pauses when they became warm, a pattern consistent with periodic breathing.14PubMed. Irregular breathing in young lambs and newborn infants during heat stress Overbundling a baby or keeping the room too warm could, in theory, make periodic breathing more frequent. Safe sleep guidelines already advise against overheating for other reasons; this adds another.
Prenatal Smoking and Breathing Control
Maternal smoking during pregnancy has measurable effects on newborn breathing regulation. Infants born to mothers who smoked showed lower respiratory drive and a blunted response to low oxygen compared to infants of nonsmoking mothers. The effect was dose-dependent: more cigarettes per day correlated with a weaker breathing response.15PubMed. Control of breathing in infants born to smoking mothers Animal studies reinforce this, showing that prenatal nicotine exposure led to a significantly higher frequency of apneas in the first two postnatal days, followed by an altered breathing pattern that emerged later in development.16PubMed. Influence of prenatal nicotine exposure on postnatal development of breathing pattern
A blunted response to low oxygen means the corrective arm of the feedback loop is weaker, which could shift the dynamics of periodic breathing in unpredictable ways. Whether this translates directly to more or worse periodic breathing in smoke-exposed infants has not been cleanly isolated from other effects of smoking on fetal development, but the disruption of the same chemoreceptor pathways that drive periodic breathing is well documented.
Periodic Breathing Versus Apnea of Prematurity
Parents and even some clinicians sometimes conflate periodic breathing with apnea of prematurity, but the two are different points on a spectrum. Periodic breathing is defined by short, rhythmic pauses typically lasting only a few seconds each, embedded in a predictable cycle. Apnea of prematurity involves longer pauses, usually defined as 20 seconds or more, or shorter pauses that come with a significant drop in heart rate or oxygen saturation. One is an expected developmental pattern; the other is a clinical event that may need intervention.
That said, the line is not always sharp. The same immature control system produces both, and a baby can transition from one to the other during a single stretch of sleep. Monitoring systems in neonatal units track both, and clinicians look at the duration of pauses, the depth of any oxygen desaturation, and whether heart rate drops below a threshold when deciding what warrants treatment.
Can Periodic Breathing Signal Illness?
Usually, periodic breathing is benign. But an increase in periodic breathing can occasionally be an early sign of infection. In extremely preterm infants, apnea events, periodic breathing exposure, and heart rate drops increased in the one to two days before a sepsis diagnosis, in infants who were not on a ventilator.17PubMed Central. Apnea, Intermittent Hypoxemia, and Bradycardia Events Predict Late-Onset Sepsis in Extremely Preterm Infants Adding periodic breathing exposure to a predictive model improved its ability to detect sepsis before clinical signs became obvious. This does not mean every uptick in periodic breathing indicates infection, but in a neonatal intensive care unit setting, a sudden change in an infant’s breathing pattern is taken seriously as a potential early warning.
The SIDS Question
For decades, researchers have explored whether periodic breathing is related to sudden infant death syndrome. An early and influential study compared nocturnal recordings from 32 infants who had experienced a near-miss SIDS event with 32 matched controls and found significantly more periodic breathing in the near-miss group across every measure: total episodes, episodes per 100 minutes of sleep, average episode duration, and duration of the longest episode.18PubMed. Periodic breathing in infants with near-miss sudden infant death syndrome
This association does not mean that periodic breathing causes SIDS. The current understanding is that both excessive periodic breathing and SIDS vulnerability share a common upstream problem: immature or dysfunctional brainstem regulation of breathing and arousal. One theoretical framework proposes that SIDS risk increases when the neural subsystems responsible for breathing control and arousal from sleep are not equally mature, a mismatch that may be worsened by prolonged parent-infant separation during sleep.19Family Relations. Potential Evolutionary, Neurophysiological, and Developmental Origins of Sudden Infant Death Syndrome and Inconsolable Crying (Colic): Is It About Controlling Breath? Periodic breathing in a normal, healthy infant is not itself a risk factor for SIDS. Excessive or prolonged periodic breathing may be a marker that the broader control system deserves closer evaluation, but it is a marker, not a cause.
Home cardiorespiratory monitors, which can detect breathing pauses and heart rate changes, have been studied as a potential tool for identifying infants at risk. Current guidance does not recommend these monitors for general SIDS prevention. They may be appropriate for infants who have had a previous apparent life-threatening event or similar episode, provided families receive adequate education on how the devices work and what their limitations are.20PubMed Central. Home Cardiorespiratory Monitoring in Infants at Risk for Sudden Infant Death Syndrome (SIDS), Apparent Life-Threatening Event (ALTE) or Brief Resolved Unexplained Event (BRUE)
Feeding and Breathing Dynamics
An aspect that sometimes catches parents off guard is how feeding changes breathing patterns. During bottle-feeding or breastfeeding, the behavioral activity of sucking and swallowing substantially suppresses the ventilatory response to carbon dioxide. One study found a roughly 74% reduction in the CO2-driven breathing response during bottle-feeding and a 55% reduction during breastfeeding.21PubMed. Effect of feeding on the chemical control of breathing in the newborn infant This means that after a feeding session, as the suppression lifts and the chemoreceptor system re-engages, there may be a period where the breathing controller is resettling into its rhythm and periodic breathing is more noticeable. It also underscores why coordination of suck-swallow-breathe is such a developmental milestone for preterm infants: the breathing control system is already unstable, and feeding adds another layer of disruption.
What Parents Can Do
For the vast majority of newborns, periodic breathing needs no treatment. Knowing it exists and what it looks like can prevent unnecessary panic. A few practical points are worth keeping in mind:
- Watch for color and recovery: If your baby’s pauses last only a few seconds and skin color stays normal, with breathing resuming on its own, this is textbook periodic breathing.
- Know the red flags: Pauses lasting 20 seconds or more, blue or gray skin discoloration, or a limp or unresponsive baby after a pause are not normal periodic breathing and warrant immediate medical attention.
- Avoid overheating: Keeping the sleep environment at a comfortable temperature (not too warm) reduces one known trigger for breathing irregularity.
- Altitude awareness: If you live at or travel to high altitude with a young infant, expect more periodic breathing and discuss any concerns with your pediatrician beforehand.
- Consumer monitors have limits: Wearable pulse oximeters and smart sock-type monitors marketed to parents can detect breathing pauses, but they are not equivalent to medical-grade devices and generate a significant number of false alarms. They should not replace medical evaluation when something seems wrong.
Premature infants discharged from the NICU with a history of significant apnea or periodic breathing may go home with a prescribed cardiorespiratory monitor. These are different from consumer products and come with training from the medical team. If your baby is sent home with one, the education you receive about responding to alarms matters as much as the device itself.