Growth spurt in babies

In the first year of life, your little explorer learns an incredible amount—no wonder, after all, there is so much to discover and experience! Every baby develops at a different pace, which is completely normal, and larger deviations are usually no cause for concern. The BMI (Body Mass Index), or Körpermasseindex in German, is also not a reliable measure for children and babies. However, there are a few guidelines. In our growth calendar, we’ve recorded the growth spurts during the first year of life.

How to recognize the growth spurts in your baby

Developmental leaps require a lot of energy and often leave your baby feeling a bit restless . This is normal, and with lots of love and physical contact, you can help him through this time. The old saying applies: "It's just a phase!" ;) There are a few more signs that your little explorer is currently going through a growth spurt:

Increased appetite
Bad mood, which is reflected in more crying and whining
Increased clinginess
Poorer and more restless sleep

Growth in the first month

Finally in the world! Your little explorer is here, and your getting-to-know-each-other time begins—how exciting. Don't be alarmed: most babies initially lose weight. This is mainly because the amniotic fluid stored in the skin disappears. After about a week, this is over. From then on, your baby gains up to 200 grams per week. Your little explorer also grows quite a bit in the first month—approximately five centimeters in body length and three centimeters in head circumference.

Development leap or growth spurt in babies?

When you hear the word "growth," you probably first think of your baby getting bigger and heavier. But in fact, the term "growth spurt" involves much more: your little explorer is learning new skills, and many new nerve cells are forming. That’s why many people also refer to it as a "developmental leap." You can read more about your baby's cognitive development.

Growth in the second month

In the second month, your baby grows by approximately three to four centimeters . There is also a lot happening on the scale: your little explorer is now comfortably continuing the 200 grams per week from the first month.

1. Growth spurt in the 5th week of life

Your baby is now perceiving more and more of their environment.
They learn to categorize sounds and visual impressions. For example, they can already recognize moving objects.
In the prone position, they can lift their little head for a few seconds.

2. Growth spurt in the 8th week of life

Now, especially your little explorer’s senses are developing: they can hear, see, and touch better and are beginning to perceive bright colors.
Your baby is getting better at holding their head up on their own.
Grasping skills also begin to develop gradually.

Growth in the third month

Your baby is still growing at a record-breaking rate in the third month. They manage approximately three to five centimeters this month and gain up to one kilogram as well. The brain also grows significantly during this time, along with head circumference. In addition, your little explorer is now putting on a good amount of baby fat. His face becomes rounder and softer, and cute little rolls are forming on his body.

3. Growth spurt in the 12th week

Your little explorer is starting to communicate more with you and now reacts much more specifically to you and his environment. He begins to babble and smile.
Your baby reaches out intentionally for objects and explores their environment.
The sleep rhythm of your baby may change. They will sleep about one to two hours less overall, but for longer stretches.

With our Milestone Cards you can easily capture the first smile, the first time sitting, and many other unforgettable firsts. We have a card set with 13 beautiful moments for you: download, print, take a photo, and enjoy! :)

Growth in the fourth month

In the fourth month, your child's growth slows down a bit. They now grow by only about two centimeters per month. Because your baby is becoming more mobile and moving around more, they also don’t gain weight as quickly.

Growth in the fifth month

It may be that the chubby cheeks from the third month are now disappearing again. For many babies, facial contours become narrower again. Nevertheless, your little explorer’s birth weight may have already doubled by now !

4. Growth spurt around week 19

This phase can last up to six weeks, and each baby develops very individually during this time.
Some babies react especially to sounds, others more to visual stimuli, or are particularly active. Many are now also in the oral phase and put everything they can get their hands on into their mouths.
The connection between cause and effect is learned.
Your little explorer is making their first attempts at rolling over.
Hand-eye coordination is improving all the time, and you'll probably need to play the drop-and-catch game more often from now on.

Growth in the sixth month

In the sixth month, your baby grows by about one and a half centimeters and gains approximately 400 grams in weight. In addition, many babies reach a major milestone in the sixth month: the first tooth appears! It often brings restlessness, increased crying, and sleepless nights. You can find out how to help your little explorer in our article on Teeth .

Growth in the seventh month

Slowly, your baby's growth is stabilizing: even in the seventh month, they grow by about one and a half centimeters and gain around 400 grams . Head circumference may increase slightly more this month than in the previous month.

5. Growth spurt around week 26

Your baby is understanding the distance between objects better and better. As a result, they might become a bit more whiny, as they get frustrated when they can’t reach things (or you).
Communication is increasing, and your little explorer is trying out new sounds.
The first roll in the prone position is successfully mastered.

Growth in the eighth month

While growth remains constant , your little explorer’s weight gain now increasingly depends on how much he moves. Maybe he is already crawling or scooting around the apartment and burning lots of energy. But the same applies here: every baby is different, and together with your doctor, you can assess individually whether everything is okay with your baby.

Growth from the ninth to the eleventh month

Between the ninth and the eleventh month, your baby's growth slows down significantly again. Overall, they will gain only about one kilogram and grow approximately three to four centimeters . At the same time, quite a bit changes externally: your little explorer is losing more and more of his baby fat and is developing the facial features of a toddler.

6. Growth spurt between the 33rd and 37th week of life

This boost lasts up to 4 weeks.
Your little explorer is becoming much more mobile, rolling from tummy to back and vice versa, and showing early signs of crawling. (Now it's definitely time to make the home childproof ! :))
In addition, he is now very adventurous—emptying boxes or looking at books with flaps and sliders is very popular.

7. Growth spurt in the 46th week of life

Your baby’s motor skills are getting better and better.
They are now not only crawling but also starting to pull themselves up on furniture.
Maybe the first steps are already possible with a hand to hold. Now pay special attention to ensure that your little explorer doesn’t fall during their adventures and can’t knock over anything that could fall on them.
By now, your baby can probably eat with a spoon and say a few words – even if in their very own baby language.

Growth in the twelfth month

The last month before your little explorer officially becomes a toddler is approaching! In the twelfth month, babies typically weigh between nine and ten kilograms, meaning their birth weight has approximately tripled . Your baby no longer looks like a baby at all, but rather like a toddler—this is because the proportion of the head to the body has changed. At birth, the head still made up a quarter of total body height; now, arms, legs, and the rest of the body have grown considerably in comparison.

8. Growth spurt starting around his 51st week of life

In this last phase, your baby begins to discover their self and personality. This means they want to do more and more on their own . And if they don’t succeed, they can sometimes have a tantrum—but the sense of achievement when they finally do is all the greater!
In addition, from now on, the first "real" word can come any day. And your little explorer can associate things with their names—for example, point to a dog when you say "dog."

The percentiles

Because growth and weight gain are so individual and different for every baby, your doctor uses a reference curve to compare your baby's values: the so-called percentile chart. This is a growth and size chart for babies and children. The word and the method come from medical statistics, and what sounds complicated is actually quite simple. Your doctor measures your little explorer's height and weight at every check-up and compares them on the percentile curve with the average values for the respective age. The percentile curve has three percentile lines: P3, P50, and P97 (shown in the graphic).

Countries where your baby's values are at P50 are exactly average—50% of all children of the same age are taller and heavier, and 50% are shorter and lighter. At P3, only 3% of all children of the same age are lighter/smaller, and at P97, only 3% are taller/heavier. Of course, height and weight do not have to be on the same percentile, which is actually very unlikely.

The BMI in children and babies

The BMI, or Body Mass Index, is not a reliable measure for assessing age-appropriate development, especially in children and babies. For your little explorer, the proper ratio of height to body weight is constantly changing, so BMI would always need to take the exact age into account. This is possible, but according to many doctors, it is not particularly meaningful. Instead, rely on your doctor’s individual assessment, for example during regular check-ups.

Important for all these curves and values is that you never look at them in isolation. Your pediatrician will interpret them as part of the bigger picture, carry out additional examinations, and, for example, include your baby's eating, sleeping, and activity habits in the assessment. Moreover, reliable evaluations only become possible after observing your baby's percentile curve over a longer period of time.

Like every child, your little explorer has their own unique pace of development and their own individual way of discovering the world. At LILLYDOO, we believe you can do this wonderfully together and wish you lots of fun!

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