A diagnosis of Pierre Robin sequence (PRS) is established when a patient exhibits the three clinical hallmarks of micrognathia (small mandible), glossoptosis (backward downward displacement of the tongue base) and airway obstruction present from birth.

Cleft palate commonly occurs, but is not a prerequisite for a diagnosis. Pierre Robin sequence may be isolated (20–40 %) or associated with a syndrome, the commonest being Stickler, foetal alcohol, Treacher-Collins and velocardiofacial syndrome. The anatomical features cause a variable degree of airway obstruction and patients may present with stridor, respiratory distress, cyanosis and signs of obstructive sleep apnoea (OSA). Patients may also exhibit other airway pathology such as laryngomalacia and subglottic stenosis. Patients are at risk of inadequate nutrition, aspiration and gastro oesophageal reflux disease. Incidence varies between 1:5,000 to 1:85,000, the range a reflection of the variable clinical presentation.