Heart Murmur Detected at Birth
Medically reviewed by Dr. Michael Okonkwo, MD, FAAP · Board-Certified Neonatologist
Content reviewed against published AAP, NIH guidelines
Last reviewed:
If your baby has been diagnosed with or you suspect heart murmur detected at birth, here is what the evidence says.
The short answer
Heart murmurs are very common in newborns and are often innocent (harmless). They are extra sounds heard with a stethoscope caused by blood flowing through the heart. Many murmurs detected at birth resolve on their own as the circulatory system transitions from fetal to newborn circulation. Your pediatrician may order an echocardiogram to confirm the murmur is innocent.
Key takeaways
- Heart murmurs are very common in newborns and are often innocent (harmless). They are extra sounds heard with a stethoscope caused by blood flowing through the heart. Many murmurs detected at birth resolve on their own as the circulatory system transitions from fetal to newborn circulation. Your pediatrician may order an echocardiogram to confirm the murmur is innocent.
- Usually normal when: An innocent murmur confirmed by echocardiogram in a well baby
- Call your doctor if: A murmur combined with difficulty feeding, rapid breathing, poor weight gain, or blue/gray skin color, which could indicate a significant heart defect
- Varies by age — see the age-by-age breakdown below
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Parents everywhere have the same worry. You are doing the right thing by looking into it.
What Parents Should Know
According to AAP, NIH guidelines, heart murmurs are very common in newborns and are often innocent (harmless). They are extra sounds heard with a stethoscope caused by blood flowing through the heart. Many murmurs detected at birth resolve on their own as the circulatory system transitions from fetal to newborn circulation. Your pediatrician may order an echocardiogram to confirm the murmur is innocent. At 0-1 month, heart murmurs are heard in many newborns during the first few days. As your baby's circulatory system transitions from the fetal pattern (where the placenta provided oxygen) to the newborn pattern (where the lungs take over), temporary murmurs are common. Many are caused by a patent ductus arteriosus (PDA), which normally closes within the first few days. If a murmur persists, your doctor may order an echocardiogram (ultrasound of the heart) to evaluate. Most murmurs found in healthy, well-appearing newborns turn out to be innocent. It is generally considered normal when an innocent murmur confirmed by echocardiogram in a well baby. However, you should contact your pediatrician promptly if a murmur combined with difficulty feeding, rapid breathing, poor weight gain, or blue/gray skin color, which could indicate a significant heart defect.
Normal vs. Concerning
By Age
What to expect by age
0-1 month
Heart murmurs are heard in many newborns during the first few days. As your baby's circulatory system transitions from the fetal pattern (where the placenta provided oxygen) to the newborn pattern (where the lungs take over), temporary murmurs are common. Many are caused by a patent ductus arteriosus (PDA), which normally closes within the first few days. If a murmur persists, your doctor may order an echocardiogram (ultrasound of the heart) to evaluate. Most murmurs found in healthy, well-appearing newborns turn out to be innocent.
1-3 months
If an echocardiogram confirmed an innocent murmur or a small, hemodynamically insignificant finding (like a small PDA or PFO), reassurance and monitoring are all that is needed. If a structural heart defect was found, a pediatric cardiologist will guide management and follow-up.
3-6 months
Innocent murmurs may come and go. They may be louder during illness or fever and softer when baby is calm. This is expected. Follow-up for any identified structural abnormality continues as recommended.
6-12 months
Innocent murmurs can persist throughout childhood and have no health significance. They do not require activity restrictions or antibiotics for dental procedures. Murmurs associated with structural defects are managed per the cardiologist's recommendations.
What to Tell Your Pediatrician
- Describe when you first noticed heart murmur detected at birth and how it has changed over time.
- Note your baby's current age and which age-specific patterns you are seeing.
- Mention if a new murmur is heard at any well-child visit.
- Mention if you want to understand what the murmur means for your baby.
- 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
- An innocent murmur confirmed by echocardiogram in a well baby
- Baby is feeding well, gaining weight, breathing comfortably, and has good skin color
- The murmur becomes softer over time
- Pediatrician is not concerned after evaluation
- A new murmur is heard at any well-child visit
- You want to understand what the murmur means for your baby
- You have a family history of heart defects
- A murmur combined with difficulty feeding, rapid breathing, poor weight gain, or blue/gray skin color, which could indicate a significant heart defect
- Baby becomes lethargic, sweaty during feeds, or has persistent rapid breathing
What You Can Do at Home
- Keep track of when you notice heart murmur detected at birth — noting the time of day, duration, and any triggers can help your pediatrician.
- Remember that an innocent murmur confirmed by echocardiogram in a well baby — this is generally within the range of normal.
- At 0-1 month, focus on observation rather than intervention unless your pediatrician advises otherwise.
- Follow any care instructions from your pediatrician. Keep a written log of symptoms to bring to appointments.
- While monitoring at home, seek immediate care if a murmur combined with difficulty feeding, rapid breathing, poor weight gain, or blue/gray skin color, which could indicate a significant heart defect.
Related Conditions
Baby Heart Murmur - Innocent vs Concerning
Heart murmurs are very common in children - up to 75% of children will have an audible murmur at some point. The vast majority are "innocent" or "functional" murmurs, meaning there is no structural heart problem. These murmurs are simply the sound of blood flowing normally through the heart and are more audible during fever, illness, or excitement. A smaller number of murmurs indicate a structural heart difference that may need monitoring or treatment. Your pediatrician can usually distinguish between the two and will refer for an echocardiogram if there is any concern.
Congenital Heart Defect Signs in Babies
Congenital heart defects (CHDs) are the most common type of birth defect, affecting about 1 in 100 babies. They range from small holes in the heart that may close on their own to complex defects requiring multiple surgeries. Early detection through pulse oximetry screening and recognizing key signs — such as blue skin, rapid breathing, poor feeding, and failure to gain weight — is critical. Advances in surgery have dramatically improved survival and quality of life.
Patent Ductus Arteriosus (PDA) in Babies
Patent ductus arteriosus (PDA) occurs when the ductus arteriosus — a blood vessel that normally closes shortly after birth — remains open. It is very common in premature babies, occurring in about 60% of babies born before 28 weeks. In full-term babies, a PDA is less common but can occur. Small PDAs may close on their own. Larger PDAs can be closed with medication, catheter procedures, or surgery, with excellent outcomes.
Related Resources
Frequently asked questions
Is heart murmur detected at birth normal?
When should I call the doctor about heart murmur detected at birth?
When is heart murmur detected at birth normal?
What causes heart murmur detected at birth?
What should I mention to my pediatrician about heart murmur detected at birth?
Is heart murmur detected at birth normal at 0-1 month?
Is heart murmur detected at birth normal at 1-3 months?
Should I go to the ER for heart murmur detected at birth?
Does heart murmur detected at birth go away on its own?
References
Doctor Visit Checklist
Bring this checklist to your next pediatrician visit to discuss Heart Murmur Detected at Birth.
Things to mention
- Describe when you first noticed heart murmur detected at birth and how it has changed over time.
- Note your baby's current age and which age-specific patterns you are seeing.
- Mention if a new murmur is heard at any well-child visit.
- Mention if you want to understand what the murmur means for your baby.
- 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
- A new murmur is heard at any well-child visit
- You want to understand what the murmur means for your baby
- You have a family history of heart defects
Urgent signs to report immediately
- A murmur combined with difficulty feeding, rapid breathing, poor weight gain, or blue/gray skin color, which could indicate a significant heart defect
- Baby becomes lethargic, sweaty during feeds, or has persistent rapid breathing
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 heart murmur detected at birth are normal. Talk to your pediatrician if a murmur combined with difficulty feeding, rapid breathing, poor weight gain, or blue/gray skin color, which could indicate a significant heart defect.
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 Medical Concerns
Baby Heart Murmur - Innocent vs Concerning
Heart murmurs are very common in children - up to 75% of children will have an audible murmur at some point. The vast majority are "innocent" or "functional" murmurs, meaning there is no structural heart problem. These murmurs are simply the sound of blood flowing normally through the heart and are more audible during fever, illness, or excitement. A smaller number of murmurs indicate a structural heart difference that may need monitoring or treatment. Your pediatrician can usually distinguish between the two and will refer for an echocardiogram if there is any concern.
Congenital Heart Defect Signs in Babies
Congenital heart defects (CHDs) are the most common type of birth defect, affecting about 1 in 100 babies. They range from small holes in the heart that may close on their own to complex defects requiring multiple surgeries. Early detection through pulse oximetry screening and recognizing key signs — such as blue skin, rapid breathing, poor feeding, and failure to gain weight — is critical. Advances in surgery have dramatically improved survival and quality of life.
Patent Ductus Arteriosus (PDA) in Babies
Patent ductus arteriosus (PDA) occurs when the ductus arteriosus — a blood vessel that normally closes shortly after birth — remains open. It is very common in premature babies, occurring in about 60% of babies born before 28 weeks. In full-term babies, a PDA is less common but can occur. Small PDAs may close on their own. Larger PDAs can be closed with medication, catheter procedures, or surgery, with excellent outcomes.
My Baby's Head Shape Looks Abnormal
Many babies develop temporary head shape irregularities that are completely normal. A cone-shaped head from vaginal delivery reshapes within days. Mild positional flattening (plagiocephaly) from sleeping on the back is very common and usually improves with repositioning and tummy time. However, head shape changes involving ridges, a persistently bulging fontanelle, or rapid head growth changes should be evaluated to rule out craniosynostosis.
Achondroplasia (Dwarfism) in Babies
Achondroplasia is the most common form of short-limbed dwarfism, affecting about 1 in 15,000 to 40,000 births. It is caused by a mutation in the FGFR3 gene and is usually apparent at birth with characteristic features including short limbs, a larger head, and a prominent forehead. Intelligence is normal. With monitoring for specific complications and supportive care, children with achondroplasia lead full, active, and independent lives.
Adenoid Hypertrophy and Breathing
Adenoids are lymphoid tissue located behind the nose that help fight infection in young children. When adenoids become enlarged (adenoid hypertrophy), they can block the nasal airway, causing chronic mouth breathing, snoring, nasal speech, and sleep-disordered breathing. Enlarged adenoids are most common between ages 2-7 and are a leading cause of obstructive sleep apnea in young children. Treatment ranges from watchful waiting and nasal steroids to surgical removal (adenoidectomy) if breathing or sleep is significantly affected.