When Birthmarks Change: What to Watch For
Medically reviewed by Dr. Sarah Chen, MD, FAAP · Board-Certified Pediatrician
Content reviewed against published AAP, NIH, AAP guidelines
Last reviewed:
Baby skin is sensitive and changes frequently. If you are noticing when birthmarks change: what to watch for, here is what you need to know.
The short answer
Most birthmarks are harmless and many change naturally as your child grows -- some fade, some darken, and some grow proportionally with the child. However, certain changes in birthmarks warrant medical attention, particularly rapid growth, ulceration, or the appearance of multiple cafe-au-lait spots. Your pediatrician monitors birthmarks at well-child visits and can determine whether any changes need further evaluation.
Key takeaways
- Most birthmarks are harmless and many change naturally as your child grows -- some fade, some darken, and some grow proportionally with the child. However, certain changes in birthmarks warrant medical attention, particularly rapid growth, ulceration, or the appearance of multiple cafe-au-lait spots. Your pediatrician monitors birthmarks at well-child visits and can determine whether any changes need further evaluation.
- Usually normal when: A hemangioma grows during the first 3-5 months of life and then gradually begins to shrink and lighten
- Call your doctor if: A hemangioma near the airway, eye, or ear is growing rapidly and could impair breathing, vision, or hearing -- seek urgent evaluation
- Varies by age — see the age-by-age breakdown below
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What Parents Should Know
According to AAP, NIH guidelines, most birthmarks are harmless and many change naturally as your child grows -- some fade, some darken, and some grow proportionally with the child. However, certain changes in birthmarks warrant medical attention, particularly rapid growth, ulceration, or the appearance of multiple cafe-au-lait spots. Your pediatrician monitors birthmarks at well-child visits and can determine whether any changes need further evaluation. At 0-3 months, some birthmarks are present at birth, while others appear in the first weeks of life. Infantile hemangiomas typically appear in the first few weeks and grow rapidly during the first 3-5 months, which can be alarming. Mongolian spots (dermal melanocytosis), which are flat, blue-gray patches commonly on the lower back and buttocks, are present at birth and are completely harmless. Stork bites (salmon patches) on the forehead, eyelids, or back of the neck are very common and usually fade within the first year. It is generally considered normal when a hemangioma grows during the first 3-5 months of life and then gradually begins to shrink and lighten. However, you should contact your pediatrician promptly if a hemangioma near the airway, eye, or ear is growing rapidly and could impair breathing, vision, or hearing -- seek urgent evaluation.
Normal vs. Concerning
By Age
What to expect by age
0-3 months
Some birthmarks are present at birth, while others appear in the first weeks of life. Infantile hemangiomas typically appear in the first few weeks and grow rapidly during the first 3-5 months, which can be alarming. Mongolian spots (dermal melanocytosis), which are flat, blue-gray patches commonly on the lower back and buttocks, are present at birth and are completely harmless. Stork bites (salmon patches) on the forehead, eyelids, or back of the neck are very common and usually fade within the first year.
3-6 months
Hemangiomas are in their most active growth phase during this period. While most are superficial and harmless, hemangiomas near the eyes, nose, mouth, or diaper area may require treatment. Port wine stains, which are flat, pink to deep purple marks caused by blood vessel malformations, do not fade on their own and grow proportionally with the child. These should be evaluated early, as treatment is most effective when started young.
6-12 months
By around 6-9 months, most hemangiomas begin to stop growing and will eventually start to shrink (involute), a process that can take several years. Congenital melanocytic nevi (brown or dark moles present at birth) should be monitored for changes in size, color, or texture. Cafe-au-lait spots -- flat, light brown patches -- are common and usually harmless, but having six or more may warrant discussion with your pediatrician.
12-24 months
Mongolian spots typically begin to fade during toddlerhood and most disappear by school age. Hemangiomas continue their slow involution phase, gradually becoming lighter and flatter. Congenital moles grow proportionally with your child, and any sudden change in color, shape, or texture should be mentioned to your pediatrician. New moles may also begin to appear, which is normal for toddlers with sun exposure.
What to Tell Your Pediatrician
- Describe when you first noticed when birthmarks change: what to watch for and how it has changed over time.
- Note your baby's current age and which age-specific patterns you are seeing.
- Mention if a hemangioma is growing rapidly, is near the eyes, nose, mouth, or airway, or is ulcerating and painful.
- Mention if your child has six or more cafe-au-lait spots, which could be associated with neurofibromatosis.
- Bring a list of any questions or observations you want to discuss at the appointment.
What Should You Do?
When to take action
- A hemangioma grows during the first 3-5 months of life and then gradually begins to shrink and lighten
- Mongolian spots gradually fade over the first few years of life
- Salmon patches (stork bites) on the forehead and eyelids become less noticeable and fade by age 1-2
- A congenital mole grows proportionally as your child grows, maintaining the same color and texture
- A hemangioma is growing rapidly, is near the eyes, nose, mouth, or airway, or is ulcerating and painful
- Your child has six or more cafe-au-lait spots, which could be associated with neurofibromatosis
- A mole or birthmark changes color, develops irregular borders, or has an uneven texture
- A port wine stain is present on the face, particularly around the eye, which may be associated with Sturge-Weber syndrome
- A hemangioma near the airway, eye, or ear is growing rapidly and could impair breathing, vision, or hearing -- seek urgent evaluation
- A birthmark or mole suddenly becomes very dark, bleeds without trauma, or develops a sore that does not heal
- A large hemangioma is ulcerating, bleeding significantly, or appears infected with increasing redness, warmth, and pain
What You Can Do at Home
- Keep track of when you notice when birthmarks change: what to watch for — noting the time of day, duration, and any triggers can help your pediatrician.
- Remember that a hemangioma grows during the first 3-5 months of life and then gradually begins to shrink and lighten — this is generally within the range of normal.
- At 0-3 months, focus on observation rather than intervention unless your pediatrician advises otherwise.
- Use fragrance-free, hypoallergenic products on your baby's skin. Avoid over-bathing — 2-3 baths per week is usually sufficient.
- While monitoring at home, seek immediate care if a hemangioma near the airway, eye, or ear is growing rapidly and could impair breathing, vision, or hearing -- seek urgent evaluation.
Related Resources
Baby Skin Conditions Guide
Visual guide to common baby skin conditions, rashes, and when to see a doctor.
Month-by-Month Development
Detailed monthly development guides from birth through 24 months.
When to Call the Doctor
General guide on when to call the pediatrician, visit urgent care, or go to the ER.
Frequently asked questions
Is when birthmarks change: what to watch for normal?
When should I call the doctor about when birthmarks change: what to watch for?
When is when birthmarks change: what to watch for normal?
What causes when birthmarks change: what to watch for?
What should I mention to my pediatrician about when birthmarks change: what to watch for?
Is when birthmarks change: what to watch for normal at 0-3 months?
Is when birthmarks change: what to watch for normal at 3-6 months?
Should I go to the ER for when birthmarks change: what to watch for?
Does when birthmarks change: what to watch for go away on its own?
References
- [1]American Academy of Pediatrics. Birthmarks in Infants. HealthyChildren.org. AAP
- [2]National Institutes of Health. Infantile Hemangiomas: Current Knowledge, Future Directions. Pediatrics, 2015. NIH
- [3]American Academy of Pediatrics. Clinical Practice Guideline for the Management of Infantile Hemangiomas. Pediatrics, 2019. AAP
Doctor Visit Checklist
Bring this checklist to your next pediatrician visit to discuss When Birthmarks Change: What to Watch For.
Things to mention
- Describe when you first noticed when birthmarks change: what to watch for and how it has changed over time.
- Note your baby's current age and which age-specific patterns you are seeing.
- Mention if a hemangioma is growing rapidly, is near the eyes, nose, mouth, or airway, or is ulcerating and painful.
- Mention if your child has six or more cafe-au-lait spots, which could be associated with neurofibromatosis.
- Bring a list of any questions or observations you want to discuss at the appointment.
Observations to share
- A hemangioma is growing rapidly, is near the eyes, nose, mouth, or airway, or is ulcerating and painful
- Your child has six or more cafe-au-lait spots, which could be associated with neurofibromatosis
- A mole or birthmark changes color, develops irregular borders, or has an uneven texture
Urgent signs to report immediately
- A hemangioma near the airway, eye, or ear is growing rapidly and could impair breathing, vision, or hearing -- seek urgent evaluation
- A birthmark or mole suddenly becomes very dark, bleeds without trauma, or develops a sore that does not heal
- A large hemangioma is ulcerating, bleeding significantly, or appears infected with increasing redness, warmth, and pain
My notes
From ismybabyalright.com — free, evidence-based baby health guides
All content follows our editorial policy and is reviewed against published clinical guidelines.
2,705 evidence-based guides6 authoritative medical sources5 medical advisory board members
Related Resources
Bottom line
Most cases of when birthmarks change: what to watch for are normal. Talk to your pediatrician if a hemangioma near the airway, eye, or ear is growing rapidly and could impair breathing, vision, or hearing -- seek urgent evaluation.
Trust your instincts. If something feels wrong, reach out to your pediatrician. Worrying about your baby means you care — that is a good thing.
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