When you take your baby to the doctor, you’ll likely hear something like, “They’re in the 49th percentile for weight and the 75 percentile for height.” And while you appreciate the information, you might wonder what it all means. What do the numbers on a baby growth chart tell you?
In this article, we’ll break down the baby growth chart and explain how it can help you track your newborn’s development over time. We’ll also look at how you can use the information to help identify potential problems.
Table of contents
- What is a baby growth chart?
- How to read a baby growth chart
- Why are growth charts used?
- How to use a growth chart at home
- Tips for helping your baby grow
What is a baby growth chart?
A baby growth chart is a tool healthcare professionals use to track the growth and development of infants during their first year of life and into early childhood.
After weighing and measuring your little one, they plot the results on a chart, which visually represents how your baby is growing compared to other children.
The most common charts in the United States are from the Centers for Disease Control and Prevention (CDC) or the World Health Organization.
Key metrics on a baby growth chart
Doctors typically use three metrics to track your baby’s growth: weight, length (or height for toddlers and older children), and head circumference. They’ll take these measurements at each well-child visit so you can see how your little one progresses over time.
However, the data isn’t all plotted on a single graph. Your doctor has four different graphs to track various aspects of your baby’s growth.
- Weight-for-age: Plots weight against age to determine how much your baby weighs compared to other babies.
- Length-for-age: Tracks the length of your baby compared to others based on their age.
- Weight-for-length: Compares the weight and the length of your baby at a specific point in time, usually during a well-child visit.
- Head circumference: Measures the size of your baby’s head (around the widest part) and compares it to other babies.
Growth charts used by doctors
While the four charts above reflect the tracked data points, not every baby is the same. Therefore, doctors use different curves based on the growth of healthy babies.
For instance, there’s a separate growth chart for boys and girls because each gender has a unique growth pattern. If you have a little girl, comparing her length to a chart of baby boys wouldn’t accurately represent how she’s growing.
Note: If your baby has been diagnosed with a condition that may affect their growth and development, their pediatrician may use a special growth chart, such as one designed for premature babies or those with Down Syndrome, instead of the standard chart.
Here’s a look at the different types of growth charts available:
- Birth to 24 Months: Boys
- Birth to 24 Months: Girls
- 2 to 20 Years: Boys
- 2 to 20 Years: Girls
- Growth charts for children with Down Syndrome
- Growth charts for premature babies
How to read a baby growth chart
With so many curved lines, labels, and numbers, baby growth charts can be confusing at first. But once you understand how to read one, you’ll easily be able to track your baby’s growth.
Here are some tips to help you better interpret the data on a growth chart:
Read the labels carefully.
The vertical axis usually represents the height or length, while the horizontal axis shows age in months. But since this could vary, check the axis labels first. Then, you’ll know what data you’re looking at.
Follow the curved lines.
The curved lines on the chart are known as “percentile curves.” They represent the distribution of growth patterns in a group of healthy babies. These charts typically show the following percentiles:
- 2nd
- 5th
- 10th
- 25th
- 50th
- 75th
- 90th
- 95th
- 98th
The percentile your little one falls under shows how they compare to other babies of the same gender and age. For example, if their weight is closest to the 25th percentile curve, 25% of the babies weigh less than your baby, and 75% weigh more.
The lower the percentile is, the smaller your baby is compared to others.
Why are growth charts used?
Growth charts are simply a tool to monitor your baby’s growth over time. They provide three important functions:
Compare growth to other kids.
Since growth charts show the average growth rate for different ages and genders, they help you see if your baby is following a growth pattern similar to that of their peers.
Track your child’s growth patterns.
You can look for trends or patterns in your baby’s growth by tracking data points at each well-child visit. You’ll be able to see your own child’s growth rate over time and compare it to their previous measurements.
Help identify potential growth problems.
Regular growth checks can help identify potential health issues early on. For example, if your baby’s weight drops significantly below their usual percentile curve or they suddenly start gaining weight faster than before, there could be an underlying health issue to address.
Concerning signs
Growth problems typically have some warning signs. If you notice any of these or have other questions about your child’s development, bring them up with their doctor.
- Weight gain stops or slows down
- Length stays the same for several months in a row
- Significant weight loss
- Head circumference stops growing or grows too quickly
- Your child is consistently in a very high or low percentile
How to use a growth chart at home
You can use a growth chart at home to track your baby’s growth between doctor visits. Before you do, ask your doctor which version of the growth charts they use in the office. That way, you’re comparing the measurements to the same standard.
Once you download the charts from the CDC or WHO, follow these steps:
- Measure your child’s length, weight, and head circumference using a scale and a soft measuring tape. Document your findings carefully.
- Plot the measurements in the appropriate category on the growth chart.
- Connect the dots to see your child’s growth curve.
- Compare the growth to look for any significant changes or questions.
- Bring any concerns or questions to your doctor.
For best results, always use the same scale. These can vary by a pound or two, affecting your child’s percentile ranking.
Things to remember about baby growth charts
While baby growth charts provide valuable information, they are just one tool to monitor your baby’s health.
Here are a few things to remember:
- Growth patterns can vary for each child and may not follow the exact percentile lines on the chart.
- Human error can occur, so double-check your measurements if one data point is significantly different.
- If your baby has been diagnosed with fetal macrosomia (meaning they weigh more than 8 pounds, 13 ounces at birth), they may go down in percentile curves before reaching their steady growth pattern.
- Use growth charts alongside other factors, such as eating habits, activity level, and health status. Tracking their developmental milestones and overall well-being is just as important.
- There’s no “perfect” percentile. As long as your baby grows steadily and is healthy, they’re on the right track regardless of where they are on the chart. Some babies are just small or large for their age, and for them, that’s normal.
- Consult your pediatrician if you have questions about your child’s growth.
Tips for helping your baby grow
While your pediatrician can provide individualized tips for your child, here are a few general recommendations to support healthy growth.
Feed newborns on demand.
Newborns have small stomachs and need to eat frequently. Let them nurse or take a bottle whenever they show signs of hunger. Wait on the feeding schedule until they’re a few months old.
Introduce solids at the right time.
Doctors typically recommend waiting to start solids until your baby is six months old. Once they start eating solid foods, introduce them to a variety of healthy foods to develop their taste buds and provide a balanced diet.
Ensure they’re sleeping well.
Sleep plays an important role in your baby’s growth, so if your little one constantly fights sleep or doesn’t get enough rest, it can affect their growth. Establish a consistent bedtime routine and make sure they’re in a comfortable sleep environment with a breathable mattress from Newton.
Encourage physical movement.
Regular tummy time can help your baby develop motor skills and strengthen their muscles. Encourage them to crawl, walk, or play actively as they grow to keep them moving.
Grow baby, grow!
A baby growth chart can help track your child’s physical growth. But remember, every child is different and may not fit perfectly into the “average” percentile. Trust your pediatrician’s advice, and consult them with any questions about your child’s growth patterns.
For more expert tips, visit the Newton website. We designed our baby sleep products to provide your little one with a safe, comfortable sleeping environment to support their growth and development.
