Overview
What are birthmarks?
Birthmarks are areas of skin that appear different from the surrounding skin due to changes in blood vessels, melanocytes (pigment cells), or other skin cells. They are typically classified into two main types:
- Vascular birthmarks – caused by abnormal blood vessel formation, appearing red, pink, or purple. Examples include hemangiomas, port-wine stains, and salmon patches.
- Pigmented birthmarks – caused by clusters of pigment cells, appearing brown, black, or blue-grey. Examples include café-au-lait spots, congenital nevi, and Mongolian spots.
Birthmarks may be present at birth or develop within the first few weeks of life, and their appearance can change over time. Some fade naturally, while others persist into adulthood.
Symptoms and Causes
Recognising the signs of birthmarks
Most birthmarks are asymptomatic, but some can cause itching, discomfort, or ulceration, particularly hemangiomas that grow rapidly.
- Vascular birthmarks: Bright red, pink, or purple patches or raised areas that may blanch under pressure. Hemangiomas may grow rapidly during the first months before gradually shrinking. Port-wine stains are flat and usually permanent.
- Pigmented birthmarks: Flat or raised patches that are brown, black, or blue-grey. Congenital nevi may vary in size and texture.
What causes birthmarks?
The exact cause of most birthmarks is unknown, but they often result from changes in skin cells or blood vessels during fetal development. Factors include:
- Genetic mutations affecting pigment or vascular cell development.
- Localised overgrowth of melanocytes or blood vessels.
- Rarely, inheritance from family history, though most birthmarks are not hereditary.
Diagnosis and Tests
Diagnosis is usually clinical, based on appearance, colour, size, and location. Healthcare professionals may use the following methods when necessary:
- Visual examination – primary assessment to identify type and characteristics.
- Dermatoscopy – magnified evaluation for pigmented birthmarks to distinguish benign lesions from potential skin cancer.
- Ultrasound or MRI – for deep or complicated hemangiomas to evaluate internal structure and potential involvement of underlying tissue.
- Biopsy – rarely required, performed if there is concern about malignancy or atypical features.
Accurate diagnosis ensures proper monitoring, informs treatment decisions, and reassures parents or patients about prognosis.
Management and Treatment
How are birthmarks managed and treated?
Most birthmarks do not require treatment. Management is tailored based on type, size, location, and potential complications:
- Observation – many birthmarks, particularly salmon patches or small hemangiomas, fade over time without intervention.
- Laser therapy – used to lighten vascular birthmarks such as port-wine stains or treat persistent hemangiomas.
- Surgical removal – may be considered for pigmented birthmarks like congenital nevi if they are large, raised, or pose a risk of malignancy.
- Topical or medical therapy – in selected cases of hemangiomas to slow growth or reduce size.
Professional evaluation is essential to avoid complications such as scarring, ulceration, or functional interference in sensitive areas (e.g., near eyes or lips).
Outlook/Prognosis
The prognosis for most birthmarks is excellent. Many vascular birthmarks, such as hemangiomas and salmon patches, shrink or disappear naturally over childhood.
- Pigmented birthmarks usually persist throughout life, but they are benign in most cases.
- Rarely, large congenital nevi carry a small risk of developing melanoma, so long-term monitoring may be advised.
- With proper treatment, cosmetic concerns can often be addressed, and functional complications are minimised.
Birthmarks are generally harmless and do not indicate underlying systemic disease, though medical assessment is recommended if changes occur in size, colour, or texture.
Prevention
Most birthmarks cannot be prevented, as they result from developmental variations in the womb. However, general skin health practices can help monitor and manage them effectively:
- Regular skin checks – to detect new or changing lesions.
- Sun protection – reducing UV exposure protects pigmented birthmarks and reduces risk of skin damage.
- Early evaluation – prompt medical assessment if lesions change, become painful, or interfere with function.
Awareness and early monitoring are key to managing birthmarks safely and addressing any potential concerns.
