Since there is a high prevalence of obesity in FM, and obesity itself is characterized by hyposomatotropism, the aim of this study was to assess IGF-1 levels and GH responsiveness in sixteen severely obese women suffering from FM, who, subdivided into two subgroups on the basis of their age-dependent IGF-1 values (> or <−2 SDS), underwent the combined GHRH plus arginine test. Here, IGF1 is linked to obesity due to melanocortin 4 receptor deficiency.