Mole (Nevus):
A parent's guide for infants and babies

A mole (nevus) is a skin growth that is the result of a cluster of color-producing cells on the skin. Moles (nevi, plural of nevus) are subdivided into those that appear after birth (acquired) and those that are present at birth (congenital). Moles typically grow at slow rates in all directions until a certain age, after which they begin to shrink in size (regress). If a mole grows at an abnormal rate, it is referred to as a dysplastic nevus.  Acquired nevi may form as the result of sun exposure or for genetic reasons. Although moles are typically flat against the skin, some can have a raised edge and potentially become irritated by friction from contact with clothes or something else that rubs against them.