GH1 and obstructive sleep apnea syndrome: We determined the effects of age on (1) the number of children diagnosed with OSA and CSA; (2) the sleep and respiratory characteristics and (3) the effects of growth hormone on OSA and CSA.<h4>Methods</h4>Retrospective review of children with PWS who underwent polysomnography pre- and post-growth hormone between January 2011 and June 2024.<h4>Results</h4>Fifty-six children (35 < 2 years; 21 ≥ 2 years) pre-growth hormone; 28 children < 2 years and 15 children ≥ 2 years after growth hormone.