Medically Reviewed by: Lesley Gilchrist
Throughout your baby’s development you’ll hear them make lots of unusual sounds both when they’re awake and asleep. Their bodies are still developing and learning the bodily functions we all take for granted and this can lead to noises which might cause you concern. One of these is Baby grunting syndrome.
Grunting baby syndrome - the medical term is Infant Dyschezia - occurs when your infant is having a poo. They may strain and make noises that suggest they're constipated, but when the poo comes out, it appears normal. This is a natural part of their development but it can be hard to see your baby in apparent distress or discomfort and you might be asking if it's serious, what you can do to help and how long it will last.
We spoke to registered midwife Lesley Gilchrist BSc MSc from My Expert Midwife and Rachel FitzD, baby and parenting expert and a retired specialist midwife, to find out all you need to know about Grunting baby syndrome.
The cause of baby grunting
Rachel FitzD tells us that Infant Dyschezia or Grunting baby syndrome is caused by your baby's muscle development and coordination. "The abdominal muscles that help us to move a poo down and out take time to develop full strength and coordination and babies haven’t yet reached that level of bowel maturity."
To compensate for this lack of abdominal oomph, babies use their diaphragm instead to shift things along and this effort puts pressure on their voice box, which results in grunting. "It can look and sound as if baby is constipated but they rarely are. It is simply the lack of mature abdominal muscles resulting in diaphragmatic effort and lots of noise."
Rachel reassures parents that it's unlikely to be causing their baby any pain or discomfort. "As uncomfortable as it looks and sounds, it is very unlikely that it hurts your baby to poo. It certainly must feel strange to have poo passing through the system after 9 non-pooing months in the womb but Grunting baby syndrome isn’t caused by difficulty in doing a poo - it is simply that baby has to do it using different muscles and that causes noise."
Why do babies grunt in their sleep?
Lesley Gilchrist notes that your baby grunting in their sleep is generally completely normal and is often a sign that they're in REM (rapid eye movement) sleep, which can lead to more movement and sounds, including grunting.
A newborn grunting and squirming while sleeping isn't normally something to worry about unless it's accompanied by other symptoms. “Your baby may also make normal grunting noises during their sleep if they are passing gas or if they are constipated,” says Lesley Gilchrist. “They may also grunt after the very occasional breath, when they are dreaming, perhaps as an expression of discomfort or content; when they are stretching or sometimes, as they are falling asleep. Rarely, grunting in a baby may be due to a problem. However, issues such as reflux, infection, certain heart conditions and respiratory distress can cause your baby to grunt.”
Why do babies grunt after feeding?
Your baby grunting after feeding is also normal and caused by their immature muscles and attempting to move food through the digestive system. As long as their poo looks normal, their digestive system is working the way it's supposed to and they're just getting used to it!
Symptoms of Grunting baby syndrome
If your newborn has Grunting baby syndrome they may experience the following:
• Grunting, crying or straining while trying to do a poo
• Their face may go red or even purple
• They may seem uncomfortable for a few minutes before having bowel movement
These symptoms can last for 10-20 minutes before your little one looks comfortable again.
Other reasons your baby may grunt
If your newborn is grunting but they aren’t experiencing any of the symptoms above, the chances are they probably don’t have Grunting baby syndrome and it could be something else.
Constipation
If your baby is grunting and straining it may be that they are constipated. This is when bowel movements become less frequent, and your baby is finding it difficult to poo. Baby constipation can be confused with Infant Dyschezia, but a constipated baby passes infrequent, small and rather solid stools. A baby with Dyschezia might grunt and strain but the poo, when it hits the nappy, will be normal and soft.
Reflux
Reflux is when your baby brings back up milk or is sick shortly after being fed, as the muscles at the base of their food pipe aren’t fully developed. It’s extremely common in babies before eight weeks old and can one of the reasons your baby is crying and potentially grunting. They could also have Silent Reflux without being sick.
Holding your baby during and after feeding for as long as possible can help prevent this, as well as making sure they sleep flat on their back. However, as your baby’s muscles develop, they should grow out of this.
Colic
Colic in babies can occur in the first few months of a baby's life which is a similar timing to Grunting baby syndrome. While experts don't really understand what causes colic, the symptoms point to abdominal discomfort, so it may be related to reflux, a milk-protein allergy, lactose intolerance, wind or stress. It can cause babies to cry around feeding times and show signs of distress similar to Infant Dyschezia. However, if your baby's fussiness ends when they pass the poo, it's likely to be Dyschezia rather than colic.
Sepsis, meningitis or heart failure
These more severe conditions can cause newborn babies to grunt, but cases are rare. If your baby is grunting, it's much more likely to be reflux, constipation or Grunting baby syndrome. However, if you notice the grunting in addition to any of the following symptoms, contact your GP immediately.
Sepsis (blood poisoning) - Signs of sepsis in babies are a blue/grey tinge in the skin, lips or tongue (on brown or black skin this might be easier to see on the palms of the hands), a rash that doesn't fade under a glass, breathlessness, grunting or breathing very fast, a weak high pitched cry (that's not like their normal cry), unusual sleepiness or floppiness. The NHS guidance on Sepsis is to call an ambulance if your baby has any of these symptoms.
Meningitis - Meningitis in babies is an infection of the protective membranes that surround the brain and spinal cord. Symptoms can include: a high pitched cry, refusing feeds, irritability, having a stiff body, being floppy or unresponsive, a bulging soft spot on the top of their head, seizures, fever, vomiting, cold hands and feet. As the NHS notes, it can also cause a sepsis rash.
Heart failure - If grunting is accompanied by other symptoms, including struggling to gain weight, shortness of breath, falling asleep during feeds or being too tired to feed, coughing, irritability, excessive sweating after feeding, or swelling in body parts, speak to your GP.
When to be concerned
Although baby grunting noises are very normal, if your baby is grunting a lot it can also be a sign that there's a problem so it's important to be able to differentiate between normal grunting noises and a grunting baby that may be unwell.
Lesley says in cases where baby grunting denotes a problem, their grunting will tend to persist (and not just happen when your baby is trying to have a poo or take a noisy breath) and be accompanied by the following signs and symptoms:
• A change in colour
• They seem distressed
• They have a high temperature
• Flaring their nostrils when they breathe in
• Other signs of laboured breathing, such as their chest/tummy ‘sucking in’ when they breathe in, may indicate more serious conditions like reflux, infection, RSV (respiratory syncytial virus), or other respiratory issues
"In such cases, or if you feel that there is something not right with your baby, always seek urgent medical advice,” says Lesley.
How is Grunting baby syndrome diagnosed?
Grunting baby syndrome is normally diagnosed through observation and questions about baby's history. For instance, your GP might want to know when baby tends to grunt, what other symptoms accompany this, and ask about their general health.
How to help a baby with Grunting baby syndrome
Rachel advises that whenever a young baby is uncomfortable or upset for any reason at all, even when it is simply caused by the sensations of doing a poo, they should be picked up and soothed. "Rocking, patting, shh-ing, massage, skin to skin and suckling (the breast, a dummy, your clean finger …) will help." As she notes, "babies cannot self-soothe and cannot learn to self-soothe by being left to their own devices, so always pick your baby up if they are upset or appear uncomfortable in any way at all. Infant Dyschezia is not caused by constipation and so shouldn’t be treated as such. Simple soothing and patience will see you and your baby through the grunts and groans safely."
How long does Grunting baby syndrome last?
While you may find it hard to watch your little one go through apparent discomfort, they will begin to stop grunting once they’ve learnt how to relax these two muscles, which is usually within a few months, so don’t panic.
“Most babies stop grunting when they are about three to four months old, or when their tummy muscles are strong enough to help with bowel movements," says Lesley.
However, if you’re concerned, whether because your baby's grunting is accompanied by other symptoms or it's lasted longer than a few months, contact your GP.
The bottom line
The main thing to remember is that Grunting baby syndrome is a perfectly normal part of your baby's development. While it might look as though it's causing them discomfort, it's just their muscles learning how to function. Provided their poos are normal and it's not accompanied by other symptoms, they should grow out of it in 3-4 months. However, if they have other symptoms or you're concerned, speak to your GP or healthcare provider.
Grunting baby syndrome FAQs
Is Grunting baby syndrome serious?
Grunting baby syndrome, or Infant Dyschezia is rarely serious unless accompanied by other symptoms, as mentioned above. If you're concerned you should always speak to your doctor but it's generally something they will grow out of.
Should I pick up a grunting baby?
As our expert, retired midwife Rachel notes, it's never a bad idea to pick up your baby. If they're showing signs of discomfort, you may be able to soothe baby by picking them up and rocking them.
About the experts
Lesley Gilchrist, BSc (Hons) Midwifery Studies, MSc Clinical Research Methods, is the CEO and founder of 'My Expert Midwife' and has been a midwife since 2003, working in some of the largest teaching hospitals in Europe. Through this time, Lesley has gained invaluable experience and insight into maternity care, labour and birth.
Rachel FitzD is a baby and parenting expert and a retired specialist midwife. She is a regular writer and presenter for The Baby Show and the author of two books, 'Your Baby Skin To Skin’ & ‘Stretched To The Limits’.
About the author
Rebecca Lancaster is a Digital Writer for Mother&Baby, drawing on ten years of parenting her two children to help others navigating their own parenting journey. As a freelance writer, she spent ten years working with leading lifestyle brands, from travel companies to food and drink start-ups, and writing everything from hotel reviews to guides to the best British cheeses. She’s particularly interested in travel and introducing her children to the excitement of visiting new places, trying different foods (less successfully) and experiencing different cultures.