The stork bite is one of the most frequent, harmless birthmarks found on newborns. Medically known as Nevus Simplex, this low-risk vascular stain is present at birth. The colloquial name comes from the folk tale that a stork delivered the baby by holding the back of its neck, leaving a mark behind. It is a benign feature of a newborn’s skin, not a sign of trauma or disease.
Defining the Stork Bite and Its Appearance
The birthmark known as a stork bite is medically termed Nevus Simplex, or Salmon Patch. This common mark is recognized by its flat, non-raised texture and its distinct pink, pale red, or salmon color. While less noticeable in darker skin tones, it still exhibits the same characteristics.
Nevus Simplex is frequently found in specific locations on a newborn’s body. Marks on the back of the neck are called “stork bites,” while those on the forehead, eyelids, or between the eyebrows are referred to as “angel kisses.” These marks are usually symmetrical and have indistinct borders, distinguishing them from other birthmarks.
The appearance of a stork bite can change temporarily based on a baby’s activity or body temperature. The patches often become darker or more prominent when the infant cries, strains, holds their breath, or becomes overheated. This normal reaction relates directly to the mark’s underlying physiological cause, which involves blood flow changes.
The Vascular Origin of Stork Bites
Stork bites are classified as vascular birthmarks, related to the blood vessels beneath the skin’s surface. The formation of Nevus Simplex is attributed to a localized dilation of tiny blood vessels called capillaries. These dilated capillaries sit close to the epidermis, the outermost layer of the skin, making them visible as a colored patch.
The mechanism involves a delay in the maturation of certain skin cells during embryonic development. This immaturity leads to a reduced ability for autonomic nerves to regulate the diameter of the dermal capillaries, causing them to remain stretched or widened. The resulting increased blood flow to the area produces the characteristic pink or red hue.
Stork bites are purely a benign capillary vascular malformation, not resulting from physical injury, trauma during birth, or any external factor. They are not associated with any underlying disease or health condition. They are present in a significant percentage of newborns, with prevalence estimates ranging from 20% to as high as 80%.
Natural Resolution and When They Fade
For most parents, the primary concern is whether the mark will disappear, and the answer is overwhelmingly positive. Stork bites are almost always temporary and require no medical treatment or intervention, such as creams or surgery. The fading occurs naturally as the infant’s skin thickens and the blood vessels mature over time.
The timeline for resolution varies significantly depending on the mark’s location. Nevus Simplex found on the face, commonly known as “angel kisses,” typically disappears completely within the first year to two years of life. Lesions on the upper eyelids are reported to resolve spontaneously in almost all cases.
Marks located on the back of the neck are more likely to persist into adulthood. While approximately 50% of these nuchal patches will fade, the remaining ones often become covered by hair and are not considered a cosmetic concern. If a mark persists on the face beyond the first year, it may still lighten over time, and a healthcare provider can discuss options like laser therapy if necessary.