What is a Hemangioma?
A hemangioma is a benign (non-cancerous) birthmark made up of extra blood vessels that clump together, appearing as a bright red, raised bump on the skin—think of it as a "strawberry mark" that typically shows up in the first few weeks after birth, grows for several months, and then gradually fades away on its own over several years. 1
Understanding the Basics
A hemangioma is fundamentally different from other birthmarks because it's actually a tumor (though benign), not just a skin discoloration or structural defect 2. Here's what makes it unique:
- When it appears: Usually shows up before a baby is 4 weeks old 3
- What it looks like: Can be bright red and raised (like a strawberry) if close to the skin surface, or bluish if deeper under the skin 1
- How it behaves: Goes through three predictable phases 3:
- Growth phase: Grows rapidly during the first 5-12 months of life
- Plateau phase: Stops growing around 12 months
- Shrinking phase: Gradually fades and flattens, with most improvement by age 4
How Common Are They?
Hemangiomas affect about 4-5% of all babies 1, making them the most common tumor of infancy 2. They're more common in:
- Girls (about 2-3 times more common than boys)
- Premature babies (affecting 22-30% of very small preterm infants)
- White/Caucasian infants 1
What Causes Them?
The exact cause isn't fully understood, but they develop from abnormal growth of blood vessel cells during infancy 1. They are not inherited in most cases (only 12% have a family history) and are not caused by anything the mother did during pregnancy 1.
Important Distinction: Not a Vascular Malformation
It's crucial to understand that hemangiomas are NOT the same as vascular malformations (like port wine stains) 1, 2. This distinction matters because:
- Hemangiomas: Grow after birth, then shrink and often disappear
- Vascular malformations: Present at birth, grow with the child, and never go away on their own 1
The confusion between these two has historically led to incorrect diagnoses and inappropriate treatments 4.
What Happens Over Time?
The good news is that 90% of hemangiomas complete their shrinking process by age 4 5. As they fade:
- The bright red color changes to milky-white or gray
- They flatten and shrink from the center outward
- The process is gradual and slower than the initial growth phase 5
However, about 70% leave behind some residual skin changes after they've gone away, such as loose skin, tiny visible blood vessels, or slight scarring 3.
When to Worry
While most hemangiomas are harmless and need no treatment, some require medical attention if they:
- Block vision, breathing, or feeding
- Are located on the face in certain patterns
- Grow very large or very quickly
- Develop sores or bleeding 2
The key message for parents: Hemangiomas are common, usually harmless birthmarks that will likely fade on their own, but early evaluation by a pediatrician is important to identify the small percentage that need closer monitoring or treatment 5.