1. Port Wine Birthmark Port Wine Birthmark Port Wine Birthmark is a blemish on the skin that is formed before birth. The color varies from pink to purple.

2. About Port-Wine Stains 0 About 3 out of every 1,000 kids are born with a port-wine stain — a birthmark that literally looks like maroon wine was spilled or splashed on the skin. 0 Port-wine stains can be anywhere on the body but most commonly are found on the face, neck, scalp, arms, or legs. They can be any size, and usually grow in proportion with a child. 0 They often change in texture over time, too — early on, they're smooth and flat but they may thicken and feel like pebbles under the skin during adulthood.

3. early on as a child, they're smooth and flat. they may become a darker red and thicken and feel like pebbles under the skin during adulthood.

4. Cause Of Port Wine 0 Port-wine stains happen when an area of skin doesn't get any supply of nerve fibers, which normally help keep blood vessels narrow. 0 When there's a lack of nerve fibers, small blood vessels (called capillaries) keep expanding, allowing a greater amount of blood to flow into the blood vessels, causing a stain to form under the skin. Birthmarks that form like this are called vascular birthmarks.