Birthmarks are marks on the skin at birth or shortly afterwards. One of the two major types of birthmarks is the vascular birthmark (the other, pigmented birthmark). Vascular birthmarks are those that arise when blood vessels do not form correctly whereas pigmented birthmarks are those that are associated with a localized overgrowth of melanocytes. They include naevus simplex (salmon patches), hemangiomas, and port-wine stains.
Naevus simplex is a birthmark that is irregularly-shaped, flat, and pink or red in color. Because of the pink or red colored patches they are colloquially called salmon patches. They form on the back of the neck, forehead, eyelids, top lip, or on the knee of certain newborns. Those that form on the back of the neck of the newborn are referred to as stork bites. They are capillary malformations and are often temporary, fading typically by the age of 1 to 2 years old. The affected skin area is not thickened and not different from the rest of the body except for the pink or red discoloration.
- nevus simplex
- naevus flammeus nuchae
- salmon patch