Birthmarks are coloured marks that form on, or just below, the surface of the skin.
The medical term for a birthmark is a naevus, or naevi (if there is more than one).
Birthmarks are not usually hereditary (passed on from your parents).
Birthmarks that develop before or shortly after birth are known as congenital birthmarks, or congenital naevi.
Types of birthmark
A birthmark that develops in the outside layer of the skin is known as an epithelial naevus, and one that occurs in the deeper layers is known as a dermal or subcutaneous naevus. There are several different types of birthmark including:
- port wine stains,
- capillary haemangioma (strawberry mark),
- cavernous haemangioma,
- congenital melanocytic naevi (CMN), and
- stork marks.
