GUIDE
The vast majority of birthmarks are harmless. A few types need monitoring or specialist referral.
You noticed a mark on your newborn that was not there yesterday — or maybe it was there at birth and nobody mentioned it. Either way, you are staring at it wondering if it means something. Odds are overwhelmingly in your favor: most birthmarks are cosmetic only and many fade completely on their own.
Your baby has a mark. Maybe it was there at birth, maybe it showed up a week later, maybe you only just noticed it because the lighting was different during tonight's bath. Your brain went straight to "is this bad?"
Here is the short answer: probably not. About 80% of newborns have at least one birthmark — salmon patches alone show up in the majority of babies born. Most birthmarks are purely cosmetic, many fade entirely, and only a handful of types need any medical attention at all.
That said, "most are fine" is not the same as "all are fine." A few types do warrant monitoring, referral, or documentation. This guide walks through every type so you know exactly which category your baby's mark falls into.
These are far and away the most common birthmark — so common that calling them a "birthmark" almost feels like an overstatement. Up to 80% of newborns have them. They are flat, pink-red patches caused by tiny blood vessels (capillaries) that are dilated near the skin surface.
You will hear two nicknames depending on location: angel kisses for patches on the forehead, eyelids, nose, or upper lip, and stork bites for patches on the back of the neck. Same thing, different spot.
They tend to get brighter when your baby cries, strains, or gets warm — which can be alarming if you were not expecting it. The blood vessels dilate further, and suddenly that faint pink smudge on the forehead looks angry red. It fades back when baby calms down.
The good news: Forehead and eyelid salmon patches almost always fade by age one to two. The not-quite-as-good-but-still-fine news: neck patches often stick around into adulthood. But they are hidden by hair, so most people never know they have one.
No treatment is needed. No specialist referral. Just a note in the chart and the knowledge that your baby has the single most common skin finding in all of newborn medicine.
These flat, blue-gray patches show up most commonly on the buttocks and lower back, but they can appear on the shoulders, flanks, and occasionally the arms or legs. They are caused by melanocytes — pigment-producing cells — that got "stuck" in the deeper layers of the skin during fetal development instead of migrating to the surface layer where they normally live.
They are extremely common in babies with darker skin tones. Up to 90% of Black, East Asian, South Asian, Hispanic, and Native American newborns have them. About 10% of white newborns have them too.
The patches range from a small coin-sized spot to large areas covering most of the lower back. They are always flat (you cannot feel an edge), and the color ranges from slate blue to blue-gray to greenish-gray. They look, frankly, like bruises. And that is exactly why they matter beyond just being a benign skin finding.
This is the birthmark you need to document. There are real, documented cases of dermal melanocytosis being mistaken for signs of physical abuse — by daycare workers, by emergency room staff, by well-meaning bystanders. Having these spots recorded in your baby's medical chart from the very first visit, with photos and descriptions, protects your family.
Dermal melanocytosis (Mongolian spots) can look exactly like bruises to anyone who is not familiar with them. There are documented cases of these spots being mistaken for signs of child abuse. Having them recorded in your baby's medical chart from birth — with photos, location, and size — protects your family. Ask your pediatrician to note them at the first visit.
Location (buttocks, lower back, flanks, shoulders), approximate size, color (blue-gray, slate blue, greenish), and whether they are single or multiple. Photos with a ruler or coin for scale are ideal. Share this documentation with daycare providers and anyone who regularly cares for your baby.
Make sure your pediatrician, any childcare providers, babysitters, and family members who watch your baby know about the spots. This is not paranoia — it is practical. A daycare worker who sees an unfamiliar blue mark and does not know about dermal melanocytosis might feel obligated to report it. A brief heads-up prevents unnecessary stress for everyone.
Track your baby's birthmarks with photos and notes in tinylog. When the pediatrician asks 'has it grown since last time?' you'll have dated photos instead of a shrug.
Infantile hemangiomas are the most common vascular tumor of infancy — which sounds scarier than it is. They are benign growths of blood vessel cells that follow a very predictable lifecycle: appear, grow, plateau, shrink. The medical term for the shrinking phase is "involution," and it is the reason most hemangiomas need nothing but patience.
They affect about 4-5% of infants and are more common in girls (3:1 ratio), premature babies, low birth weight infants, and twins. White infants are affected more often than other racial groups.
Superficial hemangiomas are the classic "strawberry" marks — raised, bright red, spongy to the touch. Deep hemangiomas sit under the skin surface and appear as bluish, soft lumps. Mixed hemangiomas have both components.
Here is the typical timeline:
| Phase | What Happens |
|---|---|
| Precursor (birth to 2 weeks) | May appear as a pale spot, a faint red mark, or a tiny cluster of blood vessels. Easy to miss or dismiss. |
| Proliferative / Growth (2 weeks to 6-9 months) | Rapid growth period. Superficial hemangiomas become raised, bright red, and spongy. Deep hemangiomas swell into bluish lumps under the skin. Most concerning growth happens in the first 3-4 months. |
| Plateau (9-12 months) | Growth stops. The hemangioma stays the same size for weeks to months. Color may start to dull slightly. |
| Involution / Shrinking (1-5+ years) | Gradual shrinking. The bright red fades to dull red, then grayish or skin-colored. The surface flattens. About 50% have significantly involuted by age 5. |
| Completed involution (by age 9-10) | About 90% are fully or nearly resolved. Some leave behind residual changes: loose skin, a faint discoloration, or visible blood vessels. Large hemangiomas are more likely to leave a trace. |
Most hemangiomas on the trunk, arms, or legs can be watched and waited out. But location matters enormously. A hemangioma near the eye can block vision during a critical development window, causing amblyopia (lazy eye) that may be permanent. One near the nose or lip can interfere with breathing or feeding. And hemangiomas in the "beard distribution" — chin, lower cheeks, front of neck — are a red flag for possible airway hemangiomas that can obstruct breathing.
The first-line treatment for problematic hemangiomas is oral propranolol, a beta-blocker that was discovered almost by accident to shrink hemangiomas. It is very effective when started early in the growth phase. This is why early referral matters — by the time a hemangioma has finished growing and started involuting on its own, the window for propranolol has partially closed.
If your baby has a hemangioma and you are not sure if its location is concerning, ask your pediatrician at the next visit. Better yet, send them a photo between visits if the growth seems rapid.
Port-wine stains are flat, red to purple marks caused by malformed capillaries in the skin. Unlike salmon patches (which they can be confused with early on), port-wine stains are permanent. They do not fade. In fact, they tend to deepen in color over time and can become thicker and more textured in adulthood if untreated.
They affect about 0.3% of newborns and can appear anywhere on the body. Most are purely cosmetic — a port-wine stain on the arm or leg needs no medical evaluation beyond documentation.
But port-wine stains on the face are a different story. A port-wine stain in the V1 dermatome — the forehead and upper eyelid area — can be associated with Sturge-Weber syndrome, a condition involving abnormal blood vessels in the brain and eye on the same side. Sturge-Weber can cause glaucoma, seizures, and developmental differences.
Not every facial port-wine stain means Sturge-Weber. The risk is highest when the stain involves the forehead and upper eyelid (V1 distribution), and lower when it only affects the cheek or jaw. But any port-wine stain on the face should be mentioned to your pediatrician, who may recommend ophthalmology screening (for glaucoma) and possibly a brain MRI.
Treatment: Pulsed dye laser is the standard treatment for port-wine stains. It works by targeting the blood vessels in the mark, causing them to shrink. Treatment is most effective when started in infancy — the skin is thinner, the blood vessels are smaller, and the stain has not yet thickened. Multiple sessions are typically needed, and results vary, but most families see significant lightening.
These flat, light brown patches — the color of coffee with milk, hence the name — are caused by a localized increase in melanin production. They have smooth, well-defined borders and uniform color. They can be present at birth or appear in the first few years of life.
One or two cafe-au-lait spots are extremely common and completely harmless. Up to 25% of healthy children have at least one. No workup needed, no monitoring needed, no referral needed.
Six or more is a different situation. Having six or more cafe-au-lait spots larger than 5mm (in children before puberty) is one of the diagnostic criteria for neurofibromatosis type 1 (NF1), a genetic condition that affects about 1 in 3,000 people. NF1 causes benign tumors to grow along nerves and can affect the skin, bones, eyes, and nervous system.
To be clear: cafe-au-lait spots alone do not diagnose NF1. The condition has multiple diagnostic criteria, and meeting just one (like the spots) triggers an evaluation, not a diagnosis. Many children with multiple cafe-au-lait spots turn out not to have NF1. But the spots are often the earliest visible sign, which is why pediatricians count them.
What to do: Count your baby's cafe-au-lait spots at each well-child visit. If the count reaches six or more spots that are each larger than 5mm, mention it to your pediatrician. They will examine for other NF1 features (freckling in the armpits or groin, Lisch nodules in the eyes) and may refer to genetics if warranted.
These are moles (nevi) that are present at birth or appear within the first few weeks of life. They are caused by a cluster of melanocytes — pigment-producing cells — that formed during fetal development. They range from light brown to very dark brown or black, and they may have hair growing from them.
Congenital nevi are classified by size:
Small congenital nevi are common (about 1% of newborns) and carry a very low melanoma risk — only marginally higher than regular acquired moles. They need routine monitoring: check for changes in color, border, symmetry, or surface texture at annual well-child visits. That is it.
Large and giant congenital nevi are rare and do carry a meaningful melanoma risk — estimated at 2-5% over a lifetime for giant nevi. These need regular follow-up with a pediatric dermatologist. Very large nevi on the head, neck, or along the spine may also need MRI screening for neurocutaneous melanosis, a condition where melanocytes are also present in the brain and spinal cord.
Giant congenital nevi can also cause significant cosmetic and psychological impact, and surgical options (staged excision, tissue expanders) are worth discussing with a specialist early, even though surgery is not always recommended or necessary.
Sebaceous nevi (nevus sebaceus of Jadassohn) are present at birth and most commonly found on the scalp, though they can appear on the face or neck. In infancy, they look like flat or slightly raised, waxy, yellowish-orange patches. A key feature: hair does not grow through them, so on the scalp they create a noticeable bald spot.
In infancy and childhood, sebaceous nevi are quiet — they just sit there. At puberty, they become thicker, bumpier, and more verrucous (wart-like) due to hormonal stimulation of the sebaceous glands within them.
The concern with sebaceous nevi is that other tumors can develop within them over time. Historically, the risk was thought to be high, but more recent studies suggest the risk of malignant transformation is low (under 1%). The most common secondary tumors are benign (trichoblastoma, syringocystadenoma papilliferum). Basal cell carcinoma can occur but is rare and almost never before adulthood.
What to do: Some dermatologists recommend prophylactic excision before puberty (when the lesion changes and becomes harder to monitor). Others take a watch-and-wait approach with regular monitoring. There is no universal consensus. Discuss the options with a dermatologist and make the decision that makes sense for your child's specific lesion — its size, location, and how comfortable you are with ongoing monitoring versus a one-time procedure.
| Type | Appearance | Cause | How Common | Does It Fade? | Treatment |
|---|---|---|---|---|---|
| Salmon Patch (stork bite / angel kiss) | Flat, pink-red patch on eyelids, forehead, upper lip, or back of neck | Dilated capillaries near the skin surface | Up to 80% of newborns | Forehead/eyelid: usually by age 1-2. Neck: often persists but hidden by hair. | None needed |
| Dermal Melanocytosis (Mongolian spots) | Flat, blue-gray patches on buttocks, lower back, flanks, or shoulders — looks like a bruise | Melanocytes trapped in deeper skin layers | Up to 90% of Black, Asian, Hispanic, and Native American newborns; ~10% of white newborns | Most fade by age 3-5. Some persist faintly. | None. Document in medical records. |
| Infantile Hemangioma (strawberry mark) | Raised, bright red, soft, spongy growth. Deep hemangiomas appear as a bluish lump under the skin. | Rapid proliferation of blood vessel cells | 4-5% of infants (more common in girls, preterm babies, and twins) | Grows 0-12 months, then slowly involutes over years. ~90% resolved by age 9-10. | Most: observation only. Near eyes/nose/airway or very large: propranolol (specialist). |
| Port-Wine Stain (nevus flammeus) | Flat, dark red or purple mark, usually on one side of the face. Deepens in color over time. | Malformed capillaries in the skin (somatic GNAQ mutation) | About 0.3% of newborns | No — permanent. Thickens and darkens with age. | Pulsed dye laser can lighten. Facial port-wine stains need Sturge-Weber screening. |
| Cafe-au-Lait Spot | Flat, light brown, oval patch — the color of coffee with milk. Smooth, uniform borders. | Localized increase in melanin production | Up to 25% of children have 1-2 spots | No — permanent, but may become less noticeable. | None for isolated spots. 6+ spots >5mm: evaluate for neurofibromatosis type 1. |
| Congenital Melanocytic Nevus | Brown to dark brown or black mole present at birth. Can range from small (<1.5cm) to giant (>20cm). May have hair. | Cluster of melanocytes present from fetal development | About 1% of newborns (giant nevi much rarer: ~1 in 20,000) | No — permanent. May lighten slightly, change texture, or develop more hair. | Small: monitor. Large/giant (>20cm): specialist monitoring for melanoma risk. |
| Sebaceous Nevus (nevus sebaceus) | Flat or slightly raised, waxy, yellowish-orange, hairless patch — usually on the scalp or face | Overgrowth of sebaceous (oil) glands from embryonic development | About 0.3% of newborns | No — permanent. Becomes thicker and more verrucous (bumpy) at puberty. | Monitor. Some dermatologists recommend excision before puberty due to small risk of secondary tumors developing within the lesion. |
| Birthmark | Monitoring | Specialist Needed? | Urgency | Follow-Up Notes |
|---|---|---|---|---|
| Salmon Patch | None needed | No | No action required | Mention at well-child visit for documentation. Most fade on their own. |
| Dermal Melanocytosis (Mongolian spots) | Document in medical records with photos | No (unless atypical location or does not fade) | Document at birth or first visit | Ensure documentation is in the chart. Revisit if not fading by age 5-6. |
| Infantile Hemangioma — uncomplicated | Track size with photos monthly during growth phase (0-6 months) | No | Routine | Mention any rapid growth or surface changes (ulceration) to pediatrician. |
| Infantile Hemangioma — high risk location | Immediate referral | Yes — pediatric dermatologist | Within first weeks of life | Near eyes: ophthalmology. Near airway: ENT. Beard area: evaluate for airway hemangiomas. May need propranolol. |
| Port-Wine Stain — body | Track color changes over time | Optional (dermatology for laser discussion) | Non-urgent | Pulsed dye laser is most effective when started early in infancy. |
| Port-Wine Stain — face (V1 distribution) | Sturge-Weber screening | Yes — ophthalmology, neurology, dermatology | Within first months of life | MRI brain, glaucoma screening, developmental monitoring if Sturge-Weber confirmed. |
| Cafe-au-Lait Spots (1-2) | None needed | No | No action required | Count any new spots at well-child visits. |
| Cafe-au-Lait Spots (6+, >5mm) | Neurofibromatosis type 1 evaluation | Yes — genetics | Non-urgent but should be evaluated | Clinical exam for other NF1 features. Genetic testing if indicated. |
| Congenital Melanocytic Nevus — small (<1.5cm) | Annual skin check | No (unless changing) | Routine | Watch for changes in color, border, symmetry, or surface texture. |
| Congenital Melanocytic Nevus — large/giant (>20cm) | Regular dermatology follow-up | Yes — pediatric dermatology | Early referral | Monitor for melanoma risk. MRI may be needed for very large or axial lesions (neurocutaneous melanosis screening). |
| Sebaceous Nevus | Annual dermatology check starting at puberty | Yes — dermatology (consider surgical referral) | Non-urgent in infancy | Some dermatologists recommend excision before puberty. Discuss with your specialist. |
These signs do not necessarily mean something is wrong — but they do mean a specialist should take a look. Early evaluation leads to better outcomes, especially for hemangiomas in risky locations.
Most birthmarks fall into the 'document it, mention it at the next visit, and do not lose sleep over it' category. Your pediatrician has seen thousands of them.
Log birthmark observations with dated photos in tinylog. Track size changes, color shifts, and any new spots — so when your doctor asks how it has changed over the last 3 months, you have an actual answer.
Put a coin or small ruler next to the birthmark and photograph it in the same lighting each time. This gives your pediatrician an objective record of whether it is growing, stable, or shrinking — way more reliable than 'I think it might be bigger?' Consistent photos are the gold standard for tracking birthmarks over time.
If your baby has blue-gray spots anywhere on their body, ask your pediatrician to note them in the chart at the very first visit — with location, size, and color. Take your own photos too. This protects your family from these benign marks being misidentified as bruises.
If a hemangioma is near your baby's eye, nose, lip, or on the chin and neck area, do not take a wait-and-see approach. The growth phase is fastest in the first 3-4 months, and treatment with propranolol is most effective when started early. Ask for a referral to pediatric dermatology within the first few weeks.
Unlike salmon patches, port-wine stains are permanent. Pulsed dye laser treatment can lighten them significantly, and it works best when started in infancy while the skin is thin and the blood vessels are small. If your baby has a port-wine stain and you are interested in treatment, ask about laser early rather than later.
One or two are nothing. But new ones can appear over time, and crossing the threshold of six spots larger than 5mm is a clinical marker that warrants a genetics evaluation for neurofibromatosis type 1. Keep a running count so your pediatrician has the full picture.
This guide is for informational purposes only and is not a substitute for professional medical advice. Birthmarks can vary significantly in appearance, and accurate classification requires examination by a qualified healthcare provider. If you have concerns about any mark on your baby's skin — especially hemangiomas near the eyes, nose, or airway, facial port-wine stains, multiple cafe-au-lait spots, or any birthmark that is changing rapidly — consult your pediatrician or a pediatric dermatologist.
