Since 2003, the GH MonitorSM, an observational registry, has collected data on pediatric subjects treated with Saizen (recombinant human growth hormone (r-hGH)) in the United States and Canada. This article provides an update on the demographic characteristics of subjects enrolled in the GHMonitorSM Registry. As of August 2007, 1733 subjects were enrolled (68.9% male). The most common primary diagnosis at screening was idiopathic growth hormone deficiency (56.5% of subjects).Of those subjects with available data, mean height standard deviation (SD) score was -2.1+/-1.0, mean weight SD score was -1.4+/-1.5, and mean body mass index SD score was -0.1+/-1.3. Among subjects in whom the presence or absence of other pituitary hormone deficiencies was recorded, 16.1% had multiple pituitary hormone deficiencies. Most patients reported high compliance with therapy (92.6% missed 0-3 doses per month); compliance was similar for all delivery devices (needle/syringe, cool.clickTM or one.clickTM) used. Two serious adverse events related to Saizen (hospitalization for placement of right frontal ventriculostomy and right frontal craniotomy for transcallosal resection of a large recurrent craniopharyngioma and left slipped capitofemoral epiphysis that required pinning of the right hip) were reported in the period from August 2006 to August 2007. This update of the GHMonitorSM Registry continues to provide insight into the characteristics of children treated with this agent and continued evidence of the efficacy and safety of Saizen in children.