Laryngomalacia
Disease Information
In-Depth
What causes congenital laryngeal stridor?
During fetal development, the structures in your baby's larynx may not fully develop. As a result, there is a weakness in these structures at birth, causing them to collapse during breathing.
- In children, a congenital laryngeal defect is the most common cause of chronic stridor.
- Sixty percent of infants born with congenital laryngeal stridor will have symptoms in the first week of life.
- Most other infants will show symptoms by 5 weeks old.
What are the symptoms of congenital laryngeal stridor?
- You'll likely be able to hear the stridor as your baby breathes in (inspiration) and out (expiration).
- The stridor changes with activity.
- The stridor is usually less noisy when your child is lying on his/her stomach.
- The stridor gets worse if your baby has an upper respiratory infection.


