Obstructive sleep apnea (OSA) is characterized by episodes of complete or partial upper airway obstruction during sleep, often resulting in gas exchange abnormalities and disrupted sleep.

Adenotonsillar hypertrophy and obesity are the major risk factors for OSA in otherwise healthy children. The contribution of each of these risk factors varies among individuals, There are other medical, neurological, skeletal, or dental conditions that reduce upper airway size which affect the neural control of the upper airway, or impact the collapsibility of the upper airway which are also risk factors for OSA. Other hereditary or genetic factors , few can be listed .