A 5-month-old infant primarily breathes through their nose. While nasal breathing is typical, occasional mouth breathing can occur. Understanding these patterns helps parents recognize what is normal and when to seek guidance.
Typical Infant Breathing
Infants are commonly referred to as obligate nasal breathers during their first few months of life, typically until around 3 to 6 months of age. This allows them to breathe continuously while feeding without interrupting their suction.
The nasal passages also play a role in filtering, warming, and humidifying the air before it reaches the lungs. At 5 months old, a baby’s breathing rate typically ranges from 20 to 40 breaths per minute when calm. Abdominal breathing is normal; you might observe their abdomen gently rising and falling with each breath as they primarily use their diaphragm.
Reasons for Mouth Breathing
A 5-month-old might breathe through their mouth for various reasons, some temporary and others more persistent. Nasal congestion, often caused by a common cold, allergies, or excess mucus, is a frequent temporary cause. Crying can also lead to temporary mouth breathing.
Less common, but more significant reasons, include enlarged adenoids or tonsils, which are tissues at the back of the nasal passage and throat that can swell due to infection or allergies, obstructing airflow. Structural issues within the nasal cavity can also cause mouth breathing. For instance, a deviated septum, where the cartilage and bone separating the nostrils are crooked, can narrow the airway. Conditions such as choanal atresia, a rare congenital condition where the back of the nose is blocked by bone or soft tissue, can also force mouth breathing. Prolonged pacifier use can also be a factor, as it can affect jaw development and lead to mouth breathing.
When to Seek Medical Advice
Observing certain signs in conjunction with mouth breathing warrants prompt medical attention for a 5-month-old. Signs of respiratory distress include an increased breathing rate, such as more than 50 breaths per minute when calm, or labored breathing. Other indicators include nasal flaring, where the nostrils widen with each breath, or retractions, which appear as the chest sinking in below the neck, under the breastbone, or between the ribs during inhalation.
Noisy breathing, such as grunting sounds with exhalation or a tight, whistling sound (wheezing), can also signal difficulty. Color changes, like a bluish tint around the mouth, on the lips, or fingernails, or pale/gray skin, suggest insufficient oxygen. Persistent mouth breathing, difficulty feeding, restless sleep, or signs of discomfort like excessive sweating on the head (without warmth) should prompt consultation with a pediatrician. Trusting parental instincts and seeking medical advice when worried about a baby’s breathing is always wise.