Birthmarks can occur anywhere on the skin, and are broadly grouped into pigmented birthmarks and vascular or red birthmarks.
Vascular/Red Birthmark are formed by the overgrowth of blood vessels anywhere on the skin, and they occur with a greater frequency in females than males. In addition Caucasian babies with a body weight of less than 2.2 pounds have a 26% chance of having vascular birthmarks. Vascular birthmarks are further grouped into macular & hemangioma.

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Macular birthmarks are caused by capillaries that are visible through the skin. Generally pink in color or shades thereof they mostly occur on the forehead, eyelids and neck regions. These generally fade away as the baby grows up. Hemangiomas are generally caused by a larger number of blood vessels getting closely packed at the surface of the skin. They usually fade with time as well.