Baby growth spurts

baby sit up on weight scales

One day you’ll look at your baby and wonder: ‘How did you get so big?’ It will seem as though it happened in the blink of an eye. Sometimes it is almost that quick – during a growth spurt, your baby will experience a rapid increase in height and weight over a relatively short period of time. And you’ll experience quite a rollercoaster, too, with your baby feeding more, and often waking at night. So brace yourself – but remember like everything, this too will pass.

What is a growth spurt in babies?

Although your child will grow continuously throughout the first few years of life, there will also be periods where it seems as though they grow overnight. You’re not imagining it – sometimes they do.

During a growth spurt, your baby’s height and weight will increase and you may suddenly notice that clothes are too small. The circumference of their head also increases. It must be all that brain growth, as you might also find that growth spurts coincide with your baby reaching a developmental milestone.

The sudden changes that accompany growth spurts can be confusing and overwhelming for both you and your baby. You might've just settled into a routine and now it seems it’s changing again. But it’s worth remembering that they are a good sign of progress.

When do growth spurts happen and how long do they last for?

Growth spurts happen right up until the teen years but during infancy they are far more frequent. Babies usually have about five growth spurts in their first year and they can last anywhere between two days and a week.

My daughter had a growth spurt at 16 weeks that lasted exactly a week. She went from sleeping through the night to needing a feed every two hours. Then after a week she just went straight back to her old routine.

As a rough guideline, you can expect to see growth spurts at:

Every child is different so don’t panic if yours doesn’t stick to this timeline. She may have more frequent growth spurts that are less noticeable or they may be less frequent but more intense.

Once your baby is eating solids, growth spurts will be less obvious as it’s harder to measure what your baby is eating.

How can I tell if my baby is having a growth spurt?

There are several signs that your baby is going through a growth spurt but the most obvious of these is an increased appetite. At times she may seem insatiable and you might find yourself feeding all day and night even every hour.

It might also be hard to settle her, even straight after a feed. Other telltale signs include:

When my son had a growth spurt at three weeks old, he bottle fed every two hours then went straight back to sleep after feeds. He was hardly awake that week.
  • Erratic sleep patterns. A hungry baby will find it hard to settle in for a good night’s sleep and might wake more during the night. Some babies find all that growing and feeding to be hard work and they’ll sleep a lot more.
  • Changes in behaviour. Your baby may be feeling just as overwhelmed as you by these sudden changes and could be clingy or grumpy.

How do I cope with the constant breastfeeding?

While sleep patterns and moods may vary from child to child, the one constant will be your baby’s appetite. It can be exhausting keeping up with a baby’s feeding demands during a growth spurt and many mums find themselves overwhelmed. You may even be tempted to give up breastfeeding at times like this. Remember that this is only temporary and will pass.

If you are mixed-feeding your baby, it’s worth trying to get some help with feeds where possible and allow yourself some respite.

If your baby is particularly clingy and not willing to take a bottle from anyone else then you might find that you have no choice but to settle in and ride it out. Cuddles and reassurance will go a long way during a growth spurt. Your partner or relative can still take the pressure off you by helping with older children or other responsibilities.

It is also possible that your baby’s appetite might rub off on you. Many mums find themselves hungrier than usual. This is entirely normal given how much work your body is doing to produce the milk your baby requires, so tuck in and make sure you’re getting plenty of rest and plenty of fuel.

Will I be able to produce enough milk for my baby during a growth spurt?

It’s easy to think that the frequency with which your baby is feeding is going to leave you short of milk. It won’t. This is the clever thing about breastfeeding: the more your baby feeds, the more milk your body produces.

The feeding is relentless and my boobs are going crazy spurting and leaking everywhere! Feeds are frequent and long and the nights are hard.

When your baby’s appetite suddenly ramps up a gear it can come as a shock. Occasionally, it can take a day or two for your milk supply to catch up to the demands of your baby’s appetite. Trust that your body knows what it needs to do.

The best way to keep producing milk is to feed your baby as often and for as long as she wants. Allowing your baby to suckle after a feed is a good way to stimulate your milk supply.

Looking after yourself will also help. Staying hydrated is especially important. Since 90% of the breastmilk leaving your body is water, it makes sense that you’ll feel thirstier and want to drink more. Keep a glass or bottle of water nearby to where you feed. (And the TV remote, and some snacks.)

Do formula-fed babies also have growth spurts?

Yes. Growth spurts are not unique to breastfed babies. Nor is the hunger. Your baby might seem hungry straight after you’ve given her a bottle. While it is fine to give a little extra milk for a day or two, be careful not to overfeed. Ask your midwife or health visitor for advice if you’re not sure.

During a growth spurt, you might be tempted to give your baby ‘hungry milk’. Be aware that this can cause upset tummies in young babies. NHS guidance does not recommend hungry milk for babies under six months. Similarly, making your baby’s formula stronger by adding less water is not a good idea. She may struggle to digest the condensed formula and it’s important to stick to the proportions stated on the tin.

How do I know if my baby is getting enough to eat?

My 11-week-old started eating hourly and being super fussy. I set up camp on the sofa and hoped it was only a phase. After six days, he just reverted back to feeding every 3 hours and now he does 6-hour stretches during the night.

The easiest way to answer this is to check nappies – if your baby has at least six wet nappies in a 24-hour period then they are likely getting enough to eat. Weight gain is the other positive sign.

Your baby’s temperament is another good indicator. If she seems grouchy, it might be because she's still hungry in which case you may need to increase the frequency or length of feeds.

What is the difference between a growth spurt and a ‘wonder week’?

Growth spurts usually refer to physical growth and an increase in weight, height and head circumference, whereas a ‘wonder week’ is the term often given to mental or developmental milestones. The term comes from the book The Wonder Weeks which pinpoints ten specific milestones or leaps in the first 20 months of a child’s life.

Do growth spurts hurt my baby?

With so much growth happening in such a short space of time and your baby being unsettled, you’d be forgiven for thinking that your child is in pain. However, there is no evidence suggesting that this is the case and the human body is designed to cope with these changes.

Could it be something other than a growth spurt?

While an increased appetite is commonly linked to growth spurts, it may also be a sign of something else. Their routine may have been upset or they may be recovering from illness. Babies tend to eat less when they are unwell and then make up for it afterwards.

If your baby’s hunger is accompanied by a high temperature, contact your GP.