My Baby Has a Sunken Chest (Pectus Excavatum)
Medically reviewed by Dr. Sarah Chen, MD, FAAP · Board-Certified Pediatrician
Content reviewed against published AAP, NIH, CDC guidelines
Last reviewed:
Your baby's physical development is unique, and concerns about has a sunken chest (pectus excavatum), here is what you need to know.
The short answer
Pectus excavatum (sunken chest) is the most common chest wall deformity, affecting about 1 in 300-400 births. Mild cases are typically cosmetic and do not affect heart or lung function. It may become more noticeable with growth. Most cases do not need treatment, but your pediatrician should monitor it.
Key takeaways
- Pectus excavatum (sunken chest) is the most common chest wall deformity, affecting about 1 in 300-400 births. Mild cases are typically cosmetic and do not affect heart or lung function. It may become more noticeable with growth. Most cases do not need treatment, but your pediatrician should monitor it.
- Usually normal when: Mild, stable indentation.
- Call your doctor if: Severe chest indentation with breathing difficulty.
- Varies by age — see the age-by-age breakdown below
“Supervised tummy time is recommended daily from the time the baby comes home from the hospital to help prevent flat head syndrome and to strengthen neck and shoulder muscles.”
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What Parents Should Know
According to AAP, NIH, CDC guidelines, pectus excavatum (sunken chest) is the most common chest wall deformity, affecting about 1 in 300-400 births. Mild cases are typically cosmetic and do not affect heart or lung function. It may become more noticeable with growth. Most cases do not need treatment, but your pediatrician should monitor it. At 0-6 months, pectus excavatum may be noticed at birth or become apparent in the early months. A mild depression in the sternum is common. Your pediatrician should note it and monitor over time. It is generally considered normal when mild, stable indentation. However, you should contact your pediatrician promptly if severe chest indentation with breathing difficulty.
Normal vs. Concerning
By Age
What to expect by age
0-6 months
Pectus excavatum may be noticed at birth or become apparent in the early months. A mild depression in the sternum is common. Your pediatrician should note it and monitor over time.
6-12 months
The indentation may become more visible as your baby grows. If breathing seems normal and your baby is gaining weight and developing well, the condition is likely mild.
12-24 months
Continue monitoring. If the indentation seems to deepen or your child has breathing concerns during activity, mention it to your pediatrician.
2-5 years
Pectus excavatum may become more prominent during growth spurts. If it is moderate to severe, a pediatric surgeon can evaluate whether intervention is needed. Most mild cases require no treatment.
What to Tell Your Pediatrician
- Describe when you first noticed has a sunken chest (pectus excavatum) and how it has changed over time.
- Note your baby's current age and which age-specific patterns you are seeing.
- Mention if indentation seems to be deepening.
- Mention if your child gets short of breath with activity.
- Let your doctor know if you have noticed any related concerns, such as changes in feeding, sleep, or movement patterns.
- Bring a list of any questions or observations you want to discuss at the appointment.
What Should You Do?
When to take action
- Mild, stable indentation.
- Normal breathing and activity tolerance.
- Normal growth and development.
- No heart or lung symptoms.
- Indentation seems to be deepening.
- Your child gets short of breath with activity.
- Heart racing or chest pain during exercise.
- Severe chest indentation with breathing difficulty.
- New onset breathing problems.
What You Can Do at Home
- Keep track of when you notice has a sunken chest (pectus excavatum) — noting the time of day, duration, and any triggers can help your pediatrician.
- Remember that mild, stable indentation — this is generally within the range of normal.
- At 0-6 months, focus on observation rather than intervention unless your pediatrician advises otherwise.
- Provide plenty of supervised floor time and tummy time to support your baby's physical development.
- While monitoring at home, seek immediate care if severe chest indentation with breathing difficulty.
Related Conditions
My Baby's Breastbone Sticks Out (Pectus Carinatum)
Pectus carinatum (protruding breastbone or "pigeon chest") is less common than pectus excavatum. In babies and toddlers, a slightly prominent sternum is often normal. True pectus carinatum typically becomes more noticeable during adolescent growth spurts. If present in infancy, your pediatrician should monitor it.
My Baby's Ribs Stick Out
Mild rib flaring (lower ribs that protrude slightly) is common in babies and toddlers, especially when lying down or with their arms up. It is often a normal anatomical variation, particularly in lean babies. However, significant rib flaring can sometimes indicate rickets (vitamin D deficiency) or core muscle weakness.
Related Resources
Milestone Checklists by Age
Track your baby's developmental milestones from birth to 5 years with age-specific checklists.
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 has a sunken chest (pectus excavatum) normal?
When should I call the doctor about has a sunken chest (pectus excavatum)?
When is has a sunken chest (pectus excavatum) normal?
What causes has a sunken chest (pectus excavatum)?
What should I mention to my pediatrician about has a sunken chest (pectus excavatum)?
Is has a sunken chest (pectus excavatum) normal at 0-6 months?
Is has a sunken chest (pectus excavatum) normal at 6-12 months?
Should I go to the ER for has a sunken chest (pectus excavatum)?
Does has a sunken chest (pectus excavatum) go away on its own?
References
Doctor Visit Checklist
Bring this checklist to your next pediatrician visit to discuss My Baby Has a Sunken Chest (Pectus Excavatum).
Things to mention
- Describe when you first noticed has a sunken chest (pectus excavatum) and how it has changed over time.
- Note your baby's current age and which age-specific patterns you are seeing.
- Mention if indentation seems to be deepening.
- Mention if your child gets short of breath with activity.
- Let your doctor know if you have noticed any related concerns, such as changes in feeding, sleep, or movement patterns.
- Bring a list of any questions or observations you want to discuss at the appointment.
Observations to share
- Indentation seems to be deepening.
- Your child gets short of breath with activity.
- Heart racing or chest pain during exercise.
Urgent signs to report immediately
- Severe chest indentation with breathing difficulty.
- New onset breathing problems.
My notes
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Related Resources
Bottom line
Most cases of has a sunken chest (pectus excavatum) are normal. Talk to your pediatrician if severe chest indentation with breathing difficulty.
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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Related Physical Concerns
My Baby's Breastbone Sticks Out (Pectus Carinatum)
Pectus carinatum (protruding breastbone or "pigeon chest") is less common than pectus excavatum. In babies and toddlers, a slightly prominent sternum is often normal. True pectus carinatum typically becomes more noticeable during adolescent growth spurts. If present in infancy, your pediatrician should monitor it.
My Baby's Ribs Stick Out
Mild rib flaring (lower ribs that protrude slightly) is common in babies and toddlers, especially when lying down or with their arms up. It is often a normal anatomical variation, particularly in lean babies. However, significant rib flaring can sometimes indicate rickets (vitamin D deficiency) or core muscle weakness.
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