Why does my baby have a ‘flat spot’ on their head?

Lifespan Osteopathy Essendon / Paediatric Osteopathy  / Why does my baby have a ‘flat spot’ on their head?

Why does my baby have a ‘flat spot’ on their head?

Many parents of  our infant patients here at Lifespan ask “why does my baby have a flat spot on their head”?

Parents are often concerned about visible changes they see to the shape of their child’s head, They want reassurance that all is OK, and this will not lead to lasting issues.

Sometimes these changes are very subtle, and other times they’re quite obvious.  

Read on to learn if you might need further assistance.


flat spot on baby head


Why does my baby have a ‘flat spot’ on their head?

The most common reason that your baby has a flat spot on their head is due to a condition called “plagiocephaly”.

“Plagiocephaly” is a general term that describes an abnormal shape of the skull.  


It literally translates to “oblique head”.


Since the “Back to Sleep” program was introduced in the 1990’s, Plagiocephaly has become more common. The Back to Sleep program was created to minimise the risk of SIDS/SUDI. It encourages parents to put their infants to sleep on their backs and not face down or in other positions. .  


Plagiocephaly occurs because the bones of a newborn’s head are quite thin and flexible.


There are two forms of plagiocephaly.


  1. Primary Plagiocephaly: 

Primary plagiocephaly is present at birth.


Two possible causes are:

  1. The way the baby was positioned in the uterus, or
  2. Complications of labour and delivery.    


It is important to remember that there is often some asymmetry, known as ‘moulding’, that occurs as part of a normal vaginal delivery.  Some of the bones in the baby’s head will overlap slightly as they pass through the birth canal. This makes their head circumference slightly smaller.  


Moulding may be seen for two or three days after birth. This is why babies often look quite different as a true newborn, compared to just a few days later.  


However, if your child’s face contains significant asymmetry beyond this time, i.e. they look quite different left to right, then there is a need for further investigation to rule out other causes.  


  1. Secondary plagiocephaly:


Secondary plagiocephaly develops after birth. 


This condition is often not diagnosed until after the first month of life. Even more commonly, secondary plagiocephaly is not detected until the infant is a few months old.  However, it may be seen earlier in some premature infants, due to their positioning in the isolette.  


This may be due to the positioning of your baby. If they spend a lot of time laying on one spot due to their inability to move to a different one, they may develop a “flat spot”. However, when mild, these cases often resolve on their own once the child attains head control and begins sitting up.


However, if the shape changes are occurring because of torticollis (a.k.a. “wry neck”), or restrictions in the subtle motions of the bones of the head, it doesn’t resolve spontaneously. Secondary Plagiocephaly can worsen as the infant grows.  



How can I treat the “flat spot” on my baby’s head?

Treatment of plagiocephaly required two things to happen.


1. Resolution of any mechanical strains that are contributing. This is where manual therapists, such as Osteopaths with an interest in Paediatrics, may be of assistance.  


Timing of treatment appears to be important. Resolving tissue strains just prior to a growth phase seems to allow the body to re-establish tissue balance in the distorted area.  Conversely, with untreated strains, the compensations made throughout the body make treatment more difficult.  


2. Getting the child to stop laying on the flat spot.  

Choosing different positions will minimise the compression on that area. This allows weight to be distributed more evenly.

A few suggestions on how to achieve this are:

  • Encouraging as much “tummy time” as possible.  Often these babies will strongly dislike this position, so alterations such as propping their chest and forearms up on a pillow, or laying on a parent’s chest, may make this more achievable.  
  • During the baby’s ‘play’ time, when they are laying on their back, try to place toys and mobiles on their non-preferred side. This encourages them not to lay on their ‘flat spot’.
  • Babies will often like to turn their head towards a door when placed in their bassinet or cot.  Placing them at a different end of their bed may mean that they turn their head away from their ‘preferred side’ in an attempt to do this.
    As they develop and become more aware, babies may like to focus on particular objects in the room.  You could try watching your baby, while they are awake but in their bed, to see if there is something they especially like to look at in the room. Then you can adjust the position of their bed in the room accordingly if need be.

Will the “flat spot” on my baby’s head get better?

When plagiocephaly is the cause of your child’s problem, their head will have a basic ‘parallelogram’ shape when viewed from above. I.e. the changes will be roughly symmetrical.  Their nose will appear straight, although the cheek on the affected side may seem fuller than the other, and their head circumference will continue to increase as they grow.  


Many babies will eventually either simply outgrow this condition without treatment as they get better head control. They may also respond favourably to treatment, and their shape changes will resolve.  


However, less than one in ten of these babies will have more severe or persistent changes, and may be suitable for assessment for devices such as a helmet.  Here in Melbourne, this service is conducted at the Royal Children’s Hospital (RCH).  


What if the “flat spot” on my baby’s head is caused by something more serious?

When assessing babies who have presented with a “flat spot” on their head, it’s important to be on the lookout for another, more serious condition. This condition is known as “craniosynostosis”.

This condition often requires surgical intervention.


Craniosynostosis is the premature closure of one or more of the bones in the child’s head.  Thankfully, this is quite a rare condition, however, it is still the most common condition seen by the craniofacial team at the RCH.  


This condition is quite close to my heart, as I was in fact born with it. I had it surgically corrected at a very early age.  Although my head shape is far from perfect,  I will be forever grateful to the skilled surgeons who performed my operation, and allowed my head to develop relatively normally.  


Ultimately, the best method for diagnosing craniosynostosis is though skull X rays and CT scans. However, there are a few ways in which this will present differently to plagiocephaly.  


The head shape of an infant with craniosynostosis, when viewed from above, will likely be asymmetrical. It is sometimes described as a ‘rhomboid’ shape. I.e. one side will appear shorter or narrower than the other when comparing left and right.  Their nose may deviate to one side, and their eye and eyebrow may look different on one side.  If undetected, they will show progressive slowing in head growth.  The only treatment for this condition is surgical, to avoid possible physical and neurological effects.  


If you’d like to learn more about plagiocephaly and craniosynostosis, you can visit the Royal Children’s Hospital page here.


In summary, if you are concerned about the “flat spot” on your baby’s head, some things you can try at home are: 

  • Getting as much supervised  “tummy time” as possible while your baby is awake.  If your baby resists this, try having them lay on your chest, or propped up on a pillow.  
  • Wearing your baby in a carrier for short periods of time, such as a Moby wrap or Ergobaby. Baby wearing  can be considered an extension of tummy time as your baby gets older and gains increased control of their head and neck.
    Also, aside from meaning that your baby is not laying on their back while being carried in these, carriers can be a lifesaver when your baby is going through a clingy phase, but you still need to get things done!
  • Changing the end of the cot/bassinet that your baby is sleeping in if necessary, or changing the position of their bed in the room. This is done to try to interest them in turning their head the other way.  
  • Placing toys, mobiles etc on their non-preferred side when they are laying on their back.


Some things to avoid:

  • The safest position for babies to sleep in is on their backs.  Avoid the temptation to have them sleep in other positions just to stop them laying on their preferred side.  
  • Pillows marketed as head positioners for babies.  Whilst they may encourage your baby not to sleep on the flat spot on their head, they generally do not comply with safe sleep guidelines.  


If you have tried all of these things, and still have some concerns, why not give us a call or book online today, to see if we might be able to help.