Growth Spurt - fact or fiction?

In this blog I am going to explore growth patterns in the first twelve months of a child’s life. I want to make it clear from the outset this is the average. Some infants are smaller, some infants are larger but the research I am sharing with you today needs to be taken into consideration whilst individuals seek input from their Child and Family Health Nurse, General Practitioner, Paediatrician and other professionals who specialize in this area.  

The growth that occurs in an infant I find fascinating. Today I am going to explore physical growth. There are many other components of child development including cognitive, psychological and social changes that occur during childhood but lets save those for another blog. 

By the way, child development is strongly influenced by genetics and the environment in which a child is raised.  70% of what it is given to us genetically is brought to fruition by our environmental experiences. These experiences are what wire our brain and the repetition is what strengthens.

So do we really have growth spurts? The answer is YES. Growth does occur in little spurts and you will find most growth in the first year occurs in the trunk. Lets explore this growth a little more. The WOrld Health Organisation (WHO) growth charts are the recommended reference that we use and lucky for us these are in our blue books (personal health record). These charts represent the growth parameters in healthy breastfed babies worldwide.

Rapid growth occurs over the first twelve months and (lets remember this is the average), some babies are on the lower or higher end of these averages.


  • Over the first five months you can expect weight gain of approximately 680g/month.
  • For the rest of the year 340g/month
  • Birth weight has tripled by one year which is approximately 9.75kg
  • Breastfed babies gain less weight than bottle fed babies.


  • 5cm/month for first six months
  • 25cm/month from 7-12 months.
  • Length increases predominately in the trunk


  • By 1 year the brain has increased in weight approximately two and a half times.
  • Head circumference increases 2cm/month to 3 months of age
  • Head circumference increases 1cm/month from 4-6 months
  • Head circumference increase 0.5cm/month from 7-12 months
  • The increase in head size reflects growth and the ongoing maturation of the nervous system.
  • Soft spots (cranial sutures) on baby’s head change.
    • The smaller one at the back of the head (posterior fontanelle) closes around 6-8weeks
    • The larger anterior fontanelle (on the top of head) closes between 12-18 months with the average being 14 months.


  • Reflexes at birth are primitive
  • Over the first twelve months reflexes become voluntary with purposeful movement.

 One last quick fact is the chest circumference is the same as the head circumference by year one. I find that fact incredible as it reflects the huge amount of development your infant has done in their first year of life. That brain has been working flat out with concurrent system developments, physical developments and functioning of the body.

 I shared this information with you today as I am fascinated by human growth but I also craved as a new mother knowing the averages which where accurate not printed on some dodgy website.  I have included by references at the bottom so you know its genuine information.  The other important element of growth is sleep. Our brains and bodies do so much growing when we are asleep. We discuss all of this in our tailored sleep consultations. Book your consultation now.


Wilson, D. (2015). Health promotion of the infant and children, In Hockenberry, M.J. & Wilson, D. (eds) 2015, Wong’s Nursing Care of Infants and Children, (10thed.) Mosby Elsevier, St Louis, pp.413-451)

Schiller, P., 2010, Early brqin development research review and update, Exchange, November/December 2010