While some babies are born with birthmarks, others develop in the weeks and months after birth. Doctors know that their appearance is due to clusters of blood vessels clumped underneath the skin, but not why or how some babies get them and others don't. Most birthmarks are completely harmless, but to be sure, talk to your pediatrician to rule out any underlying conditions.
What it is: Epidermal nevi are birthmarks of the superficial skin cells that follow a standard distribution in the skin, called Blaschko's lines. (Indicated by the swirl pattern.) They are rarely genetic.
Most children only have one area of epidermal nevus on their bodies, which can get itchy in areas of friction or sweating.
How might parents treat it? Treatment is only used to reduce any associated itch, odor, or cosmetic disfigurement and ranges from laser therapy (which flattens the area but is not permanent) to surgical removal (which is the only definitive way to remove these birthmarks).
What it is: A portwine stain is a birthmark in which a persistence of dilated or enlarged blood vessels in the skin imparts a red flush to the area. With time these areas become more red and thicker due to excess blood flow.
Portwine stains on the face can be associated with a syndrome called Sturge Weber Syndrome, in which children often develop seizures.
How might parents treat it? Portwine stains are treated by pulsed dye laser of the skin. The process is slow and takes six to 12 treatments to achieve fair lightening. Doctors may suggest beginning laser therapy on a large facial birthmark during infancy to help prevent loss of self-esteem when the child is older.
What it is: Medically referred to as a Hemangioma of Infancy (HOI), this birthmark is a tumor of rapidly growing blood vessels which enlarges in the first nine months of life and eventually clears spontaneously (without complications in most cases).
Complications can arise if the HOI is on the face, in the neck region, or in the groin. Associated malformations of the heart and eyes can accompany unusual facial hemangiomas of infancy.
How might parents treat it? Most uncomplicated HOI are treated by observation. Areas that develop open sores require pulsed dye laser therapy. When hemangiomas compress the eye, block breathing, or are growing and disfiguring the face, usage of oral and injectable medications, including steroids and interferon, can help reduce their size.