As soon as you become a parent, your little one’s happiness and health become two of your top priorities in life. A baby growth chart is one way for you and your pediatrician to make sure that your little one is growing and gaining weight as they should.

If you’re confused about how to read a growth chart, don’t worry. They’re easy to use once you get the hang of it! Plus, knowing how to read them might make you feel more at ease about your baby’s development.

Here at Mustela, we’re diving in to help you figure it all out.

What Is A Baby Growth Chart?

A growth chart might look like random numbers and lines, but for someone who knows how to read it (that will be you soon!), it’s a valuable tool for understanding and tracking a child’s growth.

Baby growth charts are typically used to measure three things: your baby’s length, weight, and head circumference. Your pediatrician will take all three of these measurements each time you and your little one go in for a checkup.

How are these measurements taken? Let’s take a look.

Length

Your baby’s length is the same as height. It’s the measurement from the top of their kissable head to the bottom of their tiny feet (their heels).

Your pediatrician will take this measurement with your baby lying down until they’re two years old. They’ll usually have to stretch your wriggling baby’s legs to get a correct measurement!

Weight

To get an accurate weight, your baby will be weighed lying on a scale — without clothes or a diaper!

Head Circumference

baby having head measured for growth chart

Can’t quite remember what “circumference” is from high school geometry? Don’t worry; we’ve got you covered! Simply put, it’s the length around a circle.

The head circumference measurement is used to determine brain size. If your baby’s head is too small or too big, it could indicate an issue with brain development.

To measure your little one’s head circumference, your pediatrician will use a measuring tape around the biggest part of their head: from the back to the forehead.

Looking at each of these measurements on a growth chart is an objective way to keep track of your baby’s growth, see how they stack up against other kids their age, and, most importantly, track patterns in their growth.

That being said, which growth chart is generally used? Good question.

Baby Growth Charts: The WHO And The CDC

There are growth charts widely used within the United States: the WHO (World Health Organization) growth chart and the CDC (Centers for Disease Control) growth chart.

There is one important difference between these two charts. The WHO growth chart shows ideal growth while the CDC chart shows average growth. Clear as mud? Let us explain a bit more.

The WHO Growth Chart

Specifically for the purpose of creating growth charts, the WHO conducted a high-quality study with babies from six countries. The resulting growth charts were released in 2006.

These charts show ideal growth for a healthy, thriving baby in good conditions.

Breastfeeding is part of “good conditions.” The WHO growth chart was made based on a study of babies who were mostly breastfed for at least four months and were still breastfeeding at twelve months.

mom breastfeeding newborn

Expert Tip: If breastfeeding is a struggle for you, talk to a lactation consultant. Fixing your baby’s latch or changing your breastfeeding position could be all it takes to make breastfeeding a great experience for both you and your little one!

While you work to correct issues, care for sore nipples by applying Mustela’s Nursing Comfort Balm. This soothing cream moisturizes and protects your nipples, eases discomfort, and helps to replenish and restore your skin during and after breastfeeding.

The CDC Growth Chart

While the WHO chart shows ideal growth in healthy babies, the CDC chart shows how typical children grow based on data collected over many years.

In other words, it’s the average growing trend of many different babies in various conditions rather than the ideal growth of healthy little ones in good conditions.

Which Growth Chart Is Better?

Your pediatrician will probably use the WHO growth chart for your baby until they are two years old, and then they’ll switch to the CDC growth chart. This is what both the CDC and the AAP (American Academy of Pediatrics) recommend.

Why? After the two-year mark, the CDC and WHO growth charts are similar. Plus, the CDC growth charts go all the way to young adulthood, while the WHO growth charts do not.

So, once you switch to the CDC chart, you’ll stick with it until your little one is 20 years old (no longer a child, but always your baby!).

How To Read A Baby Growth Chart

baby wrapped up with measuring tape for baby growth chart

Once you have your baby’s growth chart in hand, you still may not know what all the numbers mean. To help, here are six steps to reading a growth chart.

1) Choose Boy Or Girl

Baby boys and baby girls grow slightly differently. That means there are separate growth charts for boys and girls. Make sure you’re looking at the right one for your baby!

2) Find Your Baby’s Age

Find your baby’s age (in months) on the top or bottom of the chart. Keep your finger there because you’re getting ready to follow that line.

3) Find Your Baby’s Measurement

Whether you’re looking at weight, length, or head circumference, find your baby’s measurement on the far left or right side of the chart. Make sure you’re looking at the correct unit — pounds or kilograms, inches or centimeters.

Put your finger on that line as well.

4) Follow The Two Lines

Follow the line of your baby’s age and the line of their measurement to where they meet in the middle. That’s where you’ll mark the dot of their growth and where you’ll see the curved line that corresponds to your baby’s percentile.

5) Find The Percentile

Finally, trace that curved percentile line all the way toward the right side of the chart. There you’ll see the percentile numbers listed on the lines (98, 95, 90, and on down). That’s your baby’s percentile.

Using The Weight-For-Length Growth Chart

There’s one growth chart that doesn’t involve your baby’s age. This is the weight-for-length chart, and it tells you if your baby’s weight is suitable for their height and vice versa.

You’ll read this chart similarly, though. Find your baby’s weight on one side and their length on the other, and then trace those two points to where they meet to find the percentile.

What Does Percentile Mean?

parents holding baby

Now that you’ve found the magic “percentile” number on your baby’s growth chart, what does it mean?

This number tells you how your baby stacks up with other children their age. For example, if your baby is in the 90th percentile for height, that means around 90% of babies are shorter than yours and only 10% are taller than yours.

That being said, your baby’s percentile number is helpful, but it’s not the most important factor in determining if your little one is healthy. There are a couple of things to remember when thinking about percentile.

1) It’s Not A Contest

The goal of parenthood is not for your baby to rank in the highest percentile possible. It’s not a contest or an exam! A high, or increasing, percentile number doesn’t necessarily mean that your baby is extra-healthy.

There are more things to look for when it comes to overall health, which include the right number of wet and dirty diapers, activity, attention, and important developmental milestones.

While a low or high percentile number can sometimes indicate an underlying health concern, whether your baby is big or small is often simply a result of genetics!

2) Stick To The Curve

What matters more than the percentile number is that your baby stays more on less on the curve of their percentile without jumping up or down to a higher or lower percentile number. That could indicate unhealthy weight gain or weight loss.

The important thing is that your baby is consistently growing and gaining weight. That constant, healthy increase is what your pediatrician will want to see.

Look For A Happy, Healthy Little One

father and daughter smiling together

Your baby’s growth chart is a helpful indicator of their development, but it’s not the full picture.

Look out for all aspects of your little one’s health by taking care of their skin (this is especially important if they have a condition like eczema, cradle cap, or baby acne!), using natural products, keeping them safe in the sun, and caring for all of their scrapes and bruises.

If you have specific concerns about your baby’s size or development, ask your pediatrician.

Otherwise, do your best to take care of yourself with our Nursing Comfort Balm during your breastfeeding days, and be amazed as you watch your baby grow before your eyes!