The blue color on both sides of the baby’s nose may be caused by congenital heart disease, thrombocytopenic purpura, physiological factors, and so on. 1. congenital heart disease: if you suffer from congenital heart disease, especially the occurrence of a large ventricular septal defect, may lead to the occurrence of hypoxia, not only manifested in both sides of the nose green, but also accompanied by blue lips, poor peripheral circulation phenomenon. 2. Thrombocytopenic purpura: If you suffer from thrombocytopenic purpura. There will be bruises, ecchymosis, resulting in local skin color changes, scattered in various parts of the body, may be manifested in the baby nose on both sides of the blue. 3. Physiological factors: because the baby was born soon, the skin is more delicate, at the same time relatively thin, you can see the subcutaneous blood vessels, will also be manifested as a baby nose blue. If a baby has a blue nose, it is recommended to consult a doctor, improve the relevant examination, clarify the causes, and follow the doctor’s instructions for symptomatic intervention.