Is My Child Growing Well?
One of my favorite things about well-child visits with kids of all ages is reviewing growth curves with their family. It’s a privilege to watch a child grow from an infant into a teenager!
Your pediatrician uses growth curves as a tool to understand your child’s growth. There are different growth charts based on age and gender assigned at birth. The most commonly used growth charts in the U.S. are from the Centers for Disease Control (CDC) and were last updated in the year 2000.
There are different growth charts for children who have certain medical conditions that affect growth, such as Down Syndrome, to make sure these kids are growing as expected also. In addition, for infants who are born prematurely, growth curves are “adjusted” for the number of weeks early they were born.
For kids under the age of 2, we usually look at weight, height, and head circumference. For kids who are 2 to20 years, we look at weight, height, and Body Mass Index (BMI – a way to compare weight for height).
What is a growth percentile?
A growth percentile compares your child’s measurements to those of other children their age. For example, let’s say we tell you your son is in the 85th percentile for height. That means if you were to line up 100 boys your son’s age from shortest to tallest, he would be standing at number 85 in the line, with 84 boys shorter than him, and 15 boys taller. During checkups, your child’s measurements are plotted (a dot is put on the chart) for each of these measurements.
“What percentile is my infant?”
Honestly – the percentile itself doesn’t matter much to your pediatrician, and on its own, doesn’t tell us much about how healthy your child is. What we find most helpful is the trend, or line, of points on the growth curve over time. Generally, your child will stay near the same percentile as they grow through their elementary school years. Whether your baby is at the 95th percentile or 5th percentile, if their growth points are steady along this percentile over time, it’s reassuring that they’re growing as expected. If their percentile goes dramatically up or down, something might be affecting their growth that we want to look into further.
For the first 3 months of life, we expect infants to gain approximately 30g (1oz) per day. Most infants double their birth weight by about 4 to 6 months, and then triple their birth weight by 1 year.
“Does my baby’s big head mean they will be smart?”
Head circumference is different from brain capability. We measure head circumference in kids under 2 to make sure their brains are growing steadily – not too quickly, and not too slowly. The best way to help an infant/toddler with brain development is to read, talk, and play with them every day. These activities will help young kids learn lots of new words and skills that will get them ready to start school.
“How tall will my child be?”
Unfortunately, most parents leave my office without a great answer to this question. Why? While kids usually grow on the same percentile curve when they’re younger, some move up or down during the growth changes of puberty. So it’s really not possible to predict a young child’s adult height with much certainty.
One of the few tools we can use is the “mid-parental height,” which gives a genetic prediction of height.
To determine your child’s mid-parental height:
1. Add the biological mother’s and father’s heights in inches together.
2. Divide this by 2.
3. For girls – subtract 2.5 inches from #2. For boys – add 2.5 inches to #2.
This gives us an estimate, but it’s not very accurate. As an example, my own mom is 5’5”, and my dad is 6’1”. The average of those heights is 5’9”, so subtracting 2.5” from this would predict my height to be 5’ 6.5. But I grew to only 5’4”, 2.5 inches shorter than my mid-parental height. Yet the calculation may help your pediatrician understand if your child is growing in the general track predicted by their genetics.
“How long will my child keep growing?”
Girls tend to keep growing for 2 to 3 years after their first period. While stories are told about NBA players who grew well into their college years, most boys will reach their adult height before age 18.
Routine well-child visits are important for many reasons, and tracking kids’ growth over time is one of them. Feel free to ask your child’s doctor to see the growth chart at every checkup. If you have concerns about your child’s growth, please reach out to your pediatrician.
Featured Author
Dr. Lindsay Frost's biography reads: I joined the pediatrics team at Kaiser Permanente South Sacramento in 2018 to help kids thrive. Outpatient pediatrics is a unique and rewarding medical specialty. I enjoy being able to foster long-term relationships with patients and their families, providing care in both health and illness as children grow. I believe that it is important to truly partner in health care with patients and their families; this allows not only for the best possible care but also for me to continue to learn and grow as a pediatrician. A professional interest of mine is to support breastfeeding families as an International Board Certified Lactation Consultant (IBCLC). During my medical training, I also pursued a degree in public health/health promotion - a field which applies to every patient visit in pediatrics. Yet, some of my most relevant experiences as a pediatrician has come from my two children, who have “trained” me first-hand on the challenges of parenthood and in finding the balance between evidence-based recommendations and reality to achieve optimal childhood growth and development. Being part of Kaiser Permanente allows physicians and patients access to integrated care and resources that are not readily available with other health systems. Kaiser Permanente’s commitment to preventive care is also an important piece of my personal care philosophy. I am proud to be part of the team at South Sacramento and I look forward to getting to know you and your family.
Dr. Frost's full biography can be found on My Doctor Online. Disclaimer: If you have an emergency medical condition, call 911 or go to the nearest hospital. An emergency medical condition is any of the following: (1) a medical condition that manifests itself by acute symptoms of sufficient severity (including severe pain) such that you could reasonably expect the absence of immediate medical attention to result in serious jeopardy to your health or body functions or organs; (2) active labor when there isn't enough time for safe transfer to a Plan hospital (or designated hospital) before delivery, or if transfer poses a threat to your (or your unborn child's) health and safety, or (3) a mental disorder that manifests itself by acute symptoms of sufficient severity such that either you are an immediate danger to yourself or others, or you are not immediately able to provide for, or use, food, shelter, or clothing, due to the mental disorder. This information is not intended to diagnose health problems or to take the place of specific medical advice or care you receive from your physician or other health care professional. If you have persistent health problems, or if you have additional questions, please consult with your doctor. If you have questions or need more information about your medication, please speak to your pharmacist. Kaiser Permanente does not endorse the medications or products mentioned. Any trade names listed are for easy identification only.