Nevus nigromaculata generally requires surgical treatment. If it grows faster, it can be treated as soon as possible. If you grow slowly, you can wait until the child is older.

(Dr. Huang from Badachu Plastic Surgery Hospital solemnly reminds me that because I can't see the patient in person, I can't fully understand the condition. The above suggestions are for reference only. Please go to the hospital for specific diagnosis and treatment under the guidance of a doctor! )