Congenital High Airway Obstruction (CHAOS) Symptoms & Causes

In-Depth

How often does congenital high airway obstruction occur?

CHAOS was once thought to be extremely rare. Yet, more than a dozen cases have been reported since 1989.

Researchers believe that CHAOS may be more common than they realized, since many fetuses affected with this condition either do not make it to term or are born without being diagnosed.

What causes congenital high airway obstruction?

No one knows. It occurs by chance. No hereditary basis has been identified.