The North American (US and Canada) GHMonitor was initiated to assess the safety and efficacy of Saizen (somatropin [recombinant human growth hormone for injection]) for growth disorders. Between 2003 and 2005, 1057 patients were enrolled in the registry; there were more males than females (67% vs 32%), the median age was 11.2 years, and most were Caucasian (80.9%). In the GHMonitor, the cool.click needle-free device (NFD) was the most widely used Saizen delivery device (73.8%), followed by needle and syringe (19.8%) and one.click (3.3%). At enrollment, most patients were recombinant human GH (rhGH) treatment-naïve (82.8%) and patients transitioning from prior rhGH therapy tended to choose cool.click NFD (67.1%), followed by needle and syringe (27.4%), and one.click(R) (1.8%). At screening, the most common diagnoses were idiopathic growth hormone deficiency (59%), idiopathic short stature (18%), neurosecretory dysfunction (6%), and Turner syndrome (3%). Patient characteristics included bone age that was delayed an average of one year relative to chronological age, a median BMI of 16.8 kg/m2, median height standard deviation score (SDS) -2.3, and median weight SDS -1.5. Eighteen of the forty reported adverse events (45%) were felt to be associated with Saizen. Most were mild and predominantly musculoskeletal complaints, although three were reported as serious.