Hello! Pigmented birthmarks will gradually increase with age, but slowly. Nothing serious, generally no treatment. If you want to remove it, you can use laser treatment. If you want treatment, you must go to a regular hospital for treatment. It is best to use the heat generated by laser irradiation to destroy abnormal pigment cells or blood vessels in the skin without damaging normal epidermal cells and other tissues in the dermis, so as to effectively remove spots or vascular lesions without leaving scars.