EDN1 and endothelial dysfunction: All the hereinabove considered, the present study aimed to assess the effects of DRP/EE30μg combined with metformin and weight loss by means of dietary intervention on indices of endothelial dysfunction, i.e. flow-mediated dilation (FMD) and serum endothelin-1 (ET-1), serum hsCRP and lipids, and insulin resistance in young women with PCOS.