What is an infant growth spurt?
An infant growth spurt is a short period of time where a baby goes through a swift growth. Growth spurts can see both a baby’s height and weight increase rapidly.
Much like the “Terrible Twos”, baby growth spurts are something that many new parents have heard of, but when you’re in the middle of one, it can be quite tricky to spot – and feel quite worrying, too. Rest assured, though, they are completely normal and don’t last long.
According to data from the World Health Organisation (WHO), the specialized agency responsible for international public health, an average baby will triple in weight and grow between eight to 10 inches during the first 12 months of their life.
This is why you’re not imagining it when your baby seemingly outgrows their new sleepsuit in a matter of days. They really have made these impressive gains in such a short space of time.
The common ages for baby growth spurts can be:
2-3 weeks
6 weeks
3 months
6 months
As parents already know well, though, all babies are different. So, although these are the common ages, your baby’s growth spurt might not happen at these times.
“I bought my three-month-old baby a brand new, super-cute sleep-suit, with room to spare – or so I thought,” says Sarah, mom to Angus, “Just a few days later it didn’t fit him. He was really fussy and hungry around the same time, so looking back it was definitely a baby growth spurt, but back then I thought I was losing my mind. How could it fit one day and not the next?”.
Signs of a growth spurt
Amid everything else that comes with parenting an infant, it can be difficult to identify the signs of a growth spurt. But there are some key signs that can help you understand what’s going on. These include:
Cluster feeding – your new baby is 14 days old, and you’ve finally got some sort of feeding routine in place. But then, out of the blue, they start fussing to be fed every 30 minutes to an hour. This type of feeding is most common after birth, after two weeks, and then again after a month. However, it can also happen during later growth spurts. Cluster feeding can be tiring for both you and your baby but be reassured it usually only lasts a day or two.
Visible growth – your six-week-old baby seemingly outgrows their brand-new sleep-suit overnight. A good sign of a growth spurt is when clothes that seemed to have lots of room a few days previously, now look snug.
Fussiness – your three-month-old baby who’s usually full of smiles, is much grumpier than usual. They may also not seem satisfied even after being fed. Out-of-character behavior can be common during a growth spurt – they generally may seem more fussy.
Sleep pattern changes – your six-month-old baby who has been gloriously sleeping through the night (well, almost) begins waking every few hours wanting milk.
Tiredness – sleep pattern alterations can also create tiredness issues for you and your baby. Being tired will also feed into your baby becoming fussy.
If these situations do sound familiar, don’t worry. You’re not doing anything wrong. Your baby hasn’t regressed. They’re just likely going through a growth spurt. (Don’t worry either if these situations don’t sound familiar. All babies are different and will do things at their own pace.)
What ages do babies have growth spurts?
Baby growth spurts tend to happen around: the two-week, three-week, six-week, three-month, and six-month marks.
Although these are the most common times for an infant growth spurt, it’s not an exact science. For example, 2-month growth spurts and 18-month growth spurts can also occur (more on this below). No two little ones are the same, and when exactly your baby experiences a growth spurt may differ.
“By six months, I thought we’d crack it,” says Jodie, mom to Abigail, 2. “My happy, smiley little one was eating at regular times and sleeping for fairly long stretches during the night. Then all of a sudden everything changed. She was crying constantly for food and attention and was barely sleeping at all. I was so worried because I thought I’d done something wrong and that she was regressing. But it was just a normal baby growth spurt.”
How long do baby growth spurts last?
A baby growth spurt typically only lasts up to a week, but sometimes only for a couple of days. It might feel longer due to the impacts and signs of a growth spurt – and the fatigue is often difficult to manage – but it may be reassuring to learn these phases can only last a handful of days.
Remember that as babies grow, it’s not just their physical growth at play. Their overall development is evolving, too. Of course, there’s no rulebook or schedule that all babies follow, so they tend to do things when they are ready.
2-month growth spurt
Your baby’s weight gain in their second month may be around two pounds. In length, meanwhile, they could grow up to one-and-a-half inches.
Please note that there are no set parameters for baby growth, during a 2-month growth spurt or otherwise, and every infant is different. So, you may find your baby grows less than this or even a bit more.
After spending eight weeks with your little one, you’re likely used to knowing when they’re hungry, full, and even when they’re tired. They become clearer about what they want. You might notice the following when they’re hungry:
Restlessness
Mouthing
Putting hands in their mouth
Crying
At the two-month stage, your baby will typically show signs of a growth spurt in similar ways to other stages. Sleep may be disturbed, they’ll potentially be restless, their appetite can increase, and they might want to cluster feed.
18-month growth spurt
At 18 months, your toddler’s growth spurt is largely related to what’s happening with their development. You may even find this is a difficult time for them as they struggle with you not understanding what they’re trying to tell you. Unfortunately, you could witness a few tantrums due to their frustrations.
These frustrations can be understandable when you understand just how much they’re learning during this time. And the types of milestones they’re hitting at this time can be grouped into different categories:
Social and emotional
Some of the milestones in this category may include:
Pointing to things they find interesting
Playing pretend
Handing objects to people for playtime
Tantrums
Being affectionate with people they know
Language and communication
Some language and communication milestones during at 18-month growth spurt include:
Saying several single words
Saying yes and no or nodding and shaking their head
Responding to questions
Pointing to something they want
Brain development
The brain development milestones an 18-month-old might experience include:
Pointing to body parts
Recognising everyday objects and knowing their uses
Being able to scribble on their own
Movement and physical development
Physical development milestones in children of this age might include:
Independently walking (some may try running)
Walking up steps
Squatting to pick things up
Top tips for coping with infant growth spurts
These periods might feel overwhelming – and understandably so – but there are ways to help you and your baby cope.
Our top five WaterWipes tips for coping with an infant growth spurt are:
Go with the flow – this is our number one piece of advice for coping with a growth spurt. The best thing to do during infant growth spurts is to give your baby exactly what they need, adapting as you go and adapting to any behavioural shifts.
Feed on demand– allow them to feed as often and as much as they like. However when you’re feeding your infant, growth spurts will usually increase demand. Allowing them to feed when needed can help the spurt pass more comfortably.
Be flexible with naps – give them as many nap opportunities as possible. They’re extra tired, so try to help them sleep and pick up on cues when they show signs of needing extra sleep.
Be patient – if they are fussy and want more of your attention, don’t hesitate to offer them lots of cuddles. These phases can be tricky to navigate, so extra snuggles may be comforting for you both.
Look after yourself too – when you have a baby, your focus is always on them and their needs. However, it’s important to ensure you’re looking after yourself, too. Stay hydrated, try to nourish your body as best you can, and accept offered help so you can get yourself clean and rested where possible.
Just remember…
Like most things in this wonderful but tricky first year or two, it’s just a phase. They’ll get through it – and so will you.
And remember, when it comes to growth spurts, every baby is different, but if you’re concerned about your baby’s growth, reach out and speak to your doctor or health visitor. They’ll be able to provide you with advice and guidance and help reassure you about any concerns you might have.
Now you know what an infant growth spurt is, as well as the signs of a growth spurt and coping tips – why not check out our other helpful articles on our Parenting Community below:
Infant growth spurt FAQs
How do I know if my baby is having a growth spurt?
There will be a few signs of a growth spurt in your baby. You may notice they are fussier, have an increased appetite, and are more tired than usual, with disturbed sleeping patterns. You might even notice that their clothes suddenly fit more snugly.
Do babies sleep a lot during growth spurts?
Yes and no – a baby may experience disturbed sleep overnight during a growth spurt. This disturbance could be due to increased appetite and needing a feed. However, growth spurts can mean a baby is tired during the day, so they may want to nap more during these times.
How long are babies fussy during growth spurts?
An infant may be fussy for as long as their growth spurt lasts. Signs and symptoms will likely last for the duration of the spurt. This may be a couple of days, or up to a week.
What triggers a growth spurt?
Growth spurts are a natural part of their development in the first year or two. It’s the period of most-rapid growth, and babies usually triple their birth weight by the time they turn one.
