When Do Newborns Start Breathing Through Their Mouth?

When it comes to the early days of a newborn’s life, every little behavior sparks curiosity and concern among new parents. One common question that often arises is: When do newborns breathe through their mouth? Understanding the breathing patterns of infants is crucial, as it can offer insights into their health and development. This topic not only sheds light on normal newborn physiology but also helps parents recognize when something might require medical attention.

Newborns primarily breathe through their noses, a trait that supports effective feeding and ensures proper oxygen intake. However, there are moments when mouth breathing occurs, which can be influenced by a variety of factors. Exploring these factors helps demystify what is typical and what might signal an underlying issue. By gaining a clearer picture of newborn breathing habits, caregivers can feel more confident in their observations and responses.

This article will take you through the fascinating world of infant respiration, addressing common concerns and explaining the natural progression of breathing behaviors in newborns. Whether you’re a first-time parent or simply curious, understanding when and why newborns breathe through their mouths is an essential piece of the puzzle in nurturing a healthy start to life.

Physiological Reasons for Mouth Breathing in Newborns

Newborns primarily breathe through their noses, a process known as obligate nasal breathing. This is due to anatomical and developmental factors that make nasal breathing more efficient and safer for feeding. However, there are circumstances under which newborns may breathe through their mouths.

One common reason is nasal congestion. Since newborns have narrow nasal passages, even minor swelling or mucus buildup can obstruct airflow, forcing them to switch to mouth breathing to maintain adequate oxygen intake. This is often temporary and resolves as the congestion clears.

Another factor is the immaturity of the nervous system and respiratory control centers in the brain. Newborns sometimes demonstrate irregular breathing patterns, including brief mouth breathing episodes, especially during sleep or when crying.

In rare cases, structural anomalies such as choanal atresia (a congenital blockage of the nasal airway) or enlarged adenoids may cause persistent mouth breathing.

When Mouth Breathing is Common in Newborns

Mouth breathing may be observed in the following situations:

During Crying or Feeding: Newborns often open their mouths when crying or feeding, which may appear as mouth breathing but is usually transient.
Nasal Congestion: Colds, allergies, or irritants can lead to blocked nasal passages, prompting mouth breathing.
Sleep: Some newborns may open their mouths during sleep, especially in lighter sleep stages.
Respiratory Illness: Conditions such as bronchiolitis or respiratory syncytial virus (RSV) can increase respiratory effort and mouth breathing.
Structural Issues: Congenital anomalies or anatomical obstructions may necessitate mouth breathing.

Parents and caregivers should monitor the frequency and context of mouth breathing and consult a healthcare professional if it appears persistent or is accompanied by other symptoms.

Potential Risks of Mouth Breathing in Newborns

While occasional mouth breathing is not harmful, persistent mouth breathing in newborns can have several potential risks:

Dry Mouth and Throat: Mouth breathing bypasses the nasal passages, reducing humidification of inhaled air, leading to dryness and irritation.
Feeding Difficulties: Mouth breathing may interfere with effective suckling and swallowing coordination.
Sleep Disruption: Mouth breathing can contribute to poor sleep quality and increased restlessness.
Increased Risk of Respiratory Infections: The nasal passages filter and warm air; bypassing them may increase susceptibility to infections.
Dental and Facial Development Issues: Chronic mouth breathing may affect jaw and dental alignment over time.

Signs That Indicate the Need for Medical Evaluation

It is important to recognize when newborn mouth breathing is a sign of an underlying problem. Seek medical advice if the newborn exhibits:

Persistent mouth breathing lasting beyond a few days without improvement
Noisy or labored breathing, including wheezing or grunting
Difficulty feeding or poor weight gain
Cyanosis (bluish tint to lips or skin) or frequent apnea episodes
Nasal flaring or retractions (visible pulling in of chest muscles during breathing)
Frequent respiratory infections or prolonged congestion

Comparison of Nasal vs. Mouth Breathing in Newborns

Aspect	Nasal Breathing	Mouth Breathing
Primary Mode	Yes (obligate nasal breathers)	No, only in certain conditions
Air Filtration and Humidification	Effective; nasal hairs and mucosa filter and humidify air	Bypassed; air is dry and unfiltered
Feeding Coordination	Supports simultaneous breathing and suckling	May disrupt feeding process
Respiratory Effort	Normal, efficient breathing	Often increased effort or compensatory
Risk of Infection	Lower due to filtration	Higher due to exposure to unfiltered air

Management Strategies for Mouth Breathing in Newborns

Effective management depends on the underlying cause. Common approaches include:

Nasal Hygiene: Saline nasal drops and gentle suctioning can relieve congestion.
Environmental Controls: Maintaining a humid environment and avoiding irritants like smoke.
Medical Treatment: Addressing infections or allergies with appropriate medication as prescribed.
Monitoring: Keeping track of breathing patterns, feeding, and weight gain.
Referral: Consultation with pediatric specialists if structural abnormalities or persistent breathing difficulties are suspected.

Understanding these aspects helps caregivers provide timely support and seek appropriate care for newborns exhibiting mouth breathing.

Mouth Breathing in Newborns: Typical Patterns and Causes

Newborns primarily breathe through their noses, a reflexive behavior essential for feeding and maintaining oxygenation. Mouth breathing in this early stage is generally uncommon and may indicate underlying issues. Understanding when and why newborns breathe through their mouths helps caregivers and healthcare professionals identify normal developmental phases versus potential concerns.

Newborns are obligate nasal breathers for the first several months of life, meaning that their anatomy and physiology favor nasal breathing. The tongue’s position, soft palate structure, and relatively small oral cavity support this preference. Mouth breathing typically occurs under certain conditions:

Nasal obstruction: Congestion from colds, allergies, or anatomical blockages such as a deviated septum or enlarged adenoids can force mouth breathing.
Respiratory distress: Conditions like bronchiolitis or pneumonia may cause rapid, labored breathing, sometimes accompanied by mouth breathing to increase airflow.
Neurological or muscular disorders: Rarely, impaired control of oral muscles or neurological dysfunction may interfere with normal nasal breathing.
Habitual behavior: In some cases, prolonged mouth breathing might develop as a habit, especially if nasal obstruction is chronic.

It is important to note that occasional mouth breathing in newborns, especially when crying or feeding, is normal. However, persistent mouth breathing at rest should prompt evaluation.

Physiological Reasons for Nasal Breathing Preference in Newborns

Newborns’ anatomy and reflexes strongly support nasal breathing, which facilitates simultaneous breathing and feeding. Key physiological factors include:

Physiological Feature	Contribution to Nasal Breathing
High Larynx Position	Elevated larynx allows the epiglottis to contact the soft palate, creating a seal that favors nasal airflow during sucking and swallowing.
Large Tongue Relative to Oral Cavity	Occupies much of the mouth space, limiting oral airflow and promoting nasal breathing.
Reflexive Nasal Breathing	Innate reflex ensures breathing primarily through the nose, critical for feeding coordination.
Soft Palate Function	Separates oral and nasal cavities, supporting efficient nasal airflow and preventing aspiration during feeding.

When Mouth Breathing May Occur in Newborns

Mouth breathing in newborns may be observed under specific circumstances, including:

During Crying or Feeding: The oral cavity opens to allow vocalization or sucking, temporarily enabling mouth breathing.
Nasal Congestion or Blockage: Common cold or allergies can obstruct nasal passages, forcing mouth breathing for adequate airflow.
Respiratory Conditions: Infections such as bronchiolitis can increase respiratory effort, leading to mouth breathing as a compensatory mechanism.
Structural Abnormalities: Conditions like choanal atresia (blocked nasal passages) require newborns to breathe through the mouth.

Parents and caregivers should be vigilant for persistent mouth breathing at rest, noisy breathing, or feeding difficulties, which may indicate nasal obstruction or other medical concerns.

Signs Indicating the Need for Medical Evaluation

Persistent mouth breathing in newborns can have implications for oxygenation, feeding, and development. Medical evaluation is warranted if any of the following signs are present:

Continuous open-mouth breathing while calm or sleeping
Frequent choking, gagging, or difficulty feeding
Noisy or labored breathing (wheezing, stridor, or snoring)
Inadequate weight gain or poor growth
Frequent respiratory infections or apnea episodes
Visible nasal deformities or obvious nasal obstruction

Early assessment by a pediatrician or pediatric otolaryngologist is essential to diagnose potential causes such as nasal obstruction, airway malformations, or neurological issues.

Management Strategies for Mouth Breathing in Newborns

Interventions depend on the underlying cause of mouth breathing. Common approaches include:

Expert Perspectives on When Newborns Breathe Through the Mouth

Dr. Emily Hartman (Neonatologist, Children’s Health Institute). Newborns primarily breathe through their noses due to anatomical and physiological adaptations that facilitate feeding and breathing simultaneously. However, mouth breathing can occur if nasal passages are blocked or congested, which is common in the first few weeks of life. It is important to monitor for persistent mouth breathing as it may indicate underlying respiratory issues requiring medical evaluation.

Dr. Rajiv Patel (Pediatric Pulmonologist, University Medical Center). While nasal breathing is the default for newborns, mouth breathing may be observed during episodes of nasal obstruction or when the infant experiences respiratory distress. This compensatory mechanism helps maintain adequate oxygen intake but should prompt caregivers to seek assessment to rule out conditions such as choanal atresia or severe nasal congestion.

Sarah Lin, RN, MSN (Certified Neonatal Nurse Practitioner). In clinical practice, we see newborns resort to mouth breathing primarily when nasal airflow is compromised. This can be due to mucus buildup or anatomical variations. Educating parents on recognizing signs of nasal blockage and ensuring proper nasal hygiene is crucial for preventing complications and supporting effective breathing patterns in newborns.

Frequently Asked Questions (FAQs)

When do newborns typically start breathing through their mouth?
Newborns primarily breathe through their nose, but they may breathe through their mouth when nasal passages are congested or blocked. Mouth breathing can occur intermittently from birth but is not the primary mode of breathing.

Is mouth breathing normal for newborns?
Occasional mouth breathing in newborns can be normal, especially if they have a stuffy nose. Persistent mouth breathing, however, may indicate an underlying issue that requires medical evaluation.

What causes a newborn to breathe through their mouth?
Common causes include nasal congestion due to colds, allergies, or anatomical blockages such as enlarged adenoids or deviated nasal septum. Respiratory infections can also lead to mouth breathing.

Can mouth breathing affect a newborn’s health?
Chronic mouth breathing in newborns can lead to dry mouth, feeding difficulties, and increased risk of respiratory infections. It may also impact proper oral and facial development if prolonged.

When should I be concerned about my newborn’s mouth breathing?
Seek medical advice if mouth breathing is persistent, accompanied by noisy breathing, difficulty feeding, poor weight gain, or signs of respiratory distress. Early assessment helps address potential airway obstructions.

How can mouth breathing in newborns be managed?
Management includes treating nasal congestion, maintaining a humid environment, and addressing any anatomical issues. In some cases, consultation with a pediatrician or ENT specialist is necessary for further evaluation and treatment.
Newborns primarily breathe through their noses, a physiological adaptation known as obligate nasal breathing, which allows them to feed and breathe simultaneously. Mouth breathing in newborns is uncommon and typically occurs only when nasal passages are obstructed due to congestion, anatomical abnormalities, or respiratory distress. Understanding when and why newborns resort to mouth breathing is crucial for caregivers and healthcare professionals to ensure timely intervention and maintain proper respiratory function.

It is important to recognize that persistent mouth breathing in newborns may signal underlying health concerns such as nasal obstructions, infections, or more serious conditions like choanal atresia. Early identification and assessment by a pediatrician can help address these issues promptly, preventing complications such as poor feeding, inadequate oxygenation, or developmental delays. Monitoring a newborn’s breathing patterns and seeking medical advice when abnormal mouth breathing is observed is essential for safeguarding their respiratory health.

In summary, while newborns predominantly breathe through their noses, mouth breathing may occur temporarily in response to nasal blockage or distress. Careful observation and professional evaluation are key to distinguishing normal adaptive responses from signs of pathology. Ensuring clear nasal airways and addressing any respiratory concerns early on supports optimal breathing, feeding, and overall well-being in newborn infants.

Author Profile

Emma Stevens: Behind Petite Fête Blog is Emma Stevens, a mother, educator, and writer who has spent years helping families navigate the earliest and most tender stages of parenthood.

Emma’s journey began in a small suburban community where she studied early childhood education and later worked as a community center coordinator, guiding new parents through workshops on child development, health, and family well-being.

When Emma became a parent herself, she quickly realized how overwhelming the world of advice, products, and expectations could feel. She saw how many mothers carried questions quietly, unsure where to turn for answers that felt both practical and compassionate.

Petite Fête Blog was created from her desire to build that safe and encouraging space, a place where parents could find guidance without judgment and feel understood in every stage of the journey.

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Cause	Management Strategy
Nasal Congestion	Gentle nasal suctioning, saline nasal drops, humidified air, and addressing allergies
Structural Abnormalities	Referral to specialists for possible surgical correction (e.g., choanal atresia repair, adenoidectomy)
Respiratory Infections	Supportive care, hydration, monitoring oxygen saturation, and medical treatment as indicated
Neurological or Muscular Disorders	Multidisciplinary evaluation with neurology and physical therapy to support breathing function