10 Common Baby Growth Mistakes to Avoid

As a parent, you’re not expected to know about infant growth. It’s your baby’s healthcare professional who is responsible to guide you. What you may be unaware of is that mistakes can occur. And these can cause needless anxiety for parents.

Common baby growth mistakes

The assessment of infant growth is not an exact science. While there are infant growth charts and average weight gain figures which health professionals can use as a guide when assessing babies’ growth, ultimately the conclusions made rely on the health professional’s knowledge and experience. And the time and care they provide when assessing an individual baby’s growth.

Mistakes occur because of limited knowledge regarding infant feeding and growth and/or time restraints. Infant feeding aversion is one of the most common reasons parents book a Baby Care Advice consultation. In approximately 25 percent of cases, I identified growth mistakes made by health professionals consulted before me. In many of these cases, the mistakes made about baby’s growth was the reason for infant feeding practices that caused the baby to become averse to feeding.

The top 10 mistakes baby growth assessment mistakes made by health professionals occur when they…

Fail to consider false alarms and normal variations in infant growth.
Fail to check baby’s current nutritional state.
Solely use average weight gain figures when assessing growth.
Fail to take baby’s genetic endowment into account.
Fail to include baby’s length when assessing growth.
Fail to check if baby is normal weight, underweight, or overweight.
Fail to use adjusted age for preterm babies.
Incorrectly label baby as ‘failure to thrive’.
Assume more food equals faster growth.
Limit the search for poor growth reasons to medical causes.

Learning how and why these mistakes occur may enable you to identify if errors occur when your baby’s growth is assessed.

1. Failure to consider false alarms and variations in normal growth

False alarms, which give a false appearance of poor growth or weight loss from one weight check to the next. These can occur as a result of fluctuations in body fluids, weighing baby in different clothing or using different scales. (See False alarms for more.)

Variations in normal growth, such as catch-down growth; a natural decline in rate of growth as baby matures; growth plateaus that occur between growth spurts; and constitutional growth delay are common reasons for healthy babies to drink less milk and gain less weight than expected. (See Variations in normal growth for more.)

Not all health professionals consider the possibility of false alarms when assessing babies’ growth. And some appear to be unaware of the many variations of normal growth that influence the growth patterns of individual babies. As a result, these common reasons for the appearance of low or stagnant growth are often mistaken as poor growth.

2. Failure to check baby’s current nutritional state

One of the most common and most concerning of all mistakes made by health professionals is that when it appears like a baby has gained poorly - because he did not gain an expected amount - it’s automatically assumed to be because his mother is not producing enough breastmilk, or if bottle-fed, because baby is not drinking enough milk. And so, the parent is not asked relevant questions to check if this assumption is correct or not.

Asking parents questions to identify if a baby’s nutritional needs are met is an essential part of the assessment process, more so when the amount gained appears to be poor. It is necessary to do this in order to tell the difference between a genuine growth problem and a false alarm or variation in normal growth. The few minutes it takes to assess a baby’s current nutritional state can prevent an erroneous assumption about baby’s milk intake which could then be followed by inappropriate feeding advice.
You can make your own assessment of your baby’s nutritional state by checking for signs that indicate baby is well fed.

3. Solely using average weight gain figures when assessing growth

Health professionals often compare babies’ weight gain against average weight gain figures (which are based on the growth of babies of a similar age) as a quick guide during brief appointments to decide if baby is growing as expected. Doing so is not necessarily a mistake. If a baby is gaining average weight, he’s probably doing fine. Where mistakes occur is how the health professional interprets the situation when a baby doesn’t gain the expected amount.

The following are examples of common mistakes.

Some health professional wrongly believe that average weight gain figures are something that all babies must achieve. And therefore assume that if baby is not gaining average weight this signals a growth problem. Gaining less than expected weight is not evidence of a problem. It simply means more information is needed, starting with assessment of baby’s nutritional state.

The average amount of weight gained by babies in a specific time period varies between boys and girls, between breastfed and formula fed babies, between ethnic groups, and according to age. Some health professionals quote unrealistic figures. For example, they might quote the average weight gain for newborn babies for an older baby. Or the average gain for a bottle-fed baby when a baby is breastfed, or visa versa. And as a result it could be mistakenly assumed that baby is gaining poorly when this is may not be the case. (See Average weight gains to check if your health professional has quoted realistic figures.)

4. Failure to take baby’s genetic endowment into account

It’s not possible to have realistic expectations about a baby’s pattern of growth without considering his genetic endowment (inherited traits that influence his growth and other physical characteristics). Failure to do so can result in an inaccurate verdict of poor growth in cases where a baby’s weight and/or length drop to lower percentile curves on an infant growth chart, or when a baby doesn’t gain average or expected weight.

Size at birth is not a reliable indicator of a baby’s long-term growth potential. After birth a baby’s genetic endowment will influence his growth course. His growth might take on an upward or downward trajectory on an infant growth chart as his body shape and size aligns with his genetically determined path.

A baby could be born large in relation to parents’ size and drop to lower curves on an infant growth chart because he inherited ‘short’ genes from his parents. Similarly, a baby could be born small and after birth his weight and length could rise to higher percentile curves if he is genetically destined to become larger. A baby could be born skinny and gain body fat after birth. Alternatively, he could be born chubby and yet be genetically inclined to be lean because he inherited ‘skinny’ genes from his parents.

Genetically small-statured babies and genetically lean babies who where born large or chubby might display catch-down growth after birth which is frequently mistaken as poor growth.

Case study

Caden was born weighing 9 pound 5 ounces (4224grams) placing him above the 90^th percentile curve on an infant growth chart. His length was 19.25 inches (49cm), which was on the 25^th percentile. When comparing weight to length, this placed him in the overweight category. His mother’s height is 5’2” (around 20^th percentile for adult female) and father’s is 5’6” (around 5^th percentile for adult male). His health professional claimed Caden was not gaining enough weight because he was not gaining average weight and his weight had dropped to the 75^th percentile.

While it would be wise to ask questions to check on Caden’s nutritional state to confirm that he’s not underfeeding, his health professional only needed to look at his mother and ask about his father height if he was not present, or consider that Caden’s length measurement was currently sitting on the 25^th percentile, to realize that his weight was unlikely to remain above the 90^th percentile. And predict that over the next few months Caden was likely to go through catch-down growth, during which time his weight gains would in general be less than average and his weight would drop to even lower percentile curves.

Not all babies follow a typical growth pattern or gain average weight. Babies are born different shapes and sizes and they display different patterns of growth related to their unique circumstances. There are numerous growth paths that could be considered as normal growth for individual babies.

Information on baby’s weight and length at birth, his pattern of growth since birth and the height of both parents are basic information that needs to be considered when deciding whether his pattern of growth is heading towards or deviating away from his genetically determined path.

5. Failure to include baby’s length when assessing growth

Some health professionals base their assessment of a baby growth solely on weight. Not knowing a baby’s length measurement means an assessment of his growth is based on insufficient information. While it is not essential to measure a baby’s length every time he’s weighed, his length needs to be checked periodically.

If there are concerns about growth then length measurements will provide crucial information. It is essential to know baby’s length measurement in order to determine if gaining less weight than expected or weight dropping to lower percentile curves on an infant growth chart is a problem or not.

If a baby gains less than expected, more information is required to make an accurate assessment of the situation. Length measurement is necessary to accurately determine if a baby is underweight, overweight or normal weight.

Weight sitting within two growth curves above or below baby’s length on an infant growth chart is considered to be within a normal range.

If a baby’s weight is higher growth curve compared to his length, then weight dropping growth curves might indicate catch-down growth. Catch-down growth is easily distinguishable from poor growth by the fact that baby shows signs of being well fed.

If a baby’s weight sits two or more growth curves lower than his length further investigation is required to determine if growth is poor or not. The first step is to ask questions to determine if baby is showing signs of being well fed before jumping to conclusions that baby is not eating enough. If well fed, then questions about genetic endowment might point to a genetic inclination to be lean.

Anytime a baby doesn’t gain weight as expected or if his weight drops percentile curves, its important that his nutritional state is checked.

6. Failure to check if baby is normal weight, underweight or overweight

Identifying if a baby is normal weight, underweight or overweight is helpful when concerns are raised about the amount of weight gained or about weight dropping percentile curves on an infant growth chart. It is also helpful information to have when establishing realistic expectations about baby’s future growth course.

Using sight is not a reliable way to identify if a baby’s size is within a normal weight range. We are so accustomed to images of chubby babies being represented as the epitome of healthy growth that most of us are unable to recognize when a baby is overweight.

You can determine if your baby is overweight, underweight or normal weight -provided you have his length measurement taken at the same time as his weight measurement – by using one of following methods.

Weight-to-length standard deviation score
Body mass index standard deviation score

Knowing whether your baby is underweight, overweight or normal weight can help when deciding whether fluctuations in growth might indicate a problem. For example:

Is it a problem that overweight or obese baby gains less than average weight, or that his weight drops to a lower percentile curve? Probably not! Gaining less than average could be due to catch-down growth, which occurs once the reason for an excess accumulation of body fat has been corrected.

What if a normal weight or underweight baby gains less than expected or weight drops to lower percentile curve? This may or may not signal a problem. The first step is to assess baby’s current nutritional state before assuming baby is underfeeding.

7. Failure to use adjusted age for a preterm baby

Most infant growth charts, with the exception of those specifically designed for preterm babies, are intended for babies born at term (i.e. 37 or more weeks gestation). Infant growth charts for term babies can be used to track the growth of preterm babies provided baby’s adjusted age is used (i.e. baby’s actual age minus the number of weeks he was born preterm).

In some cases health professionals incorrectly use a preterm baby’s actual age when marking his measurements on an infant growth chart designed for term babies. Using actual age means a preterm baby’s growth is being compared against other babies who may have had between 1 and 3 months or more growing time in the womb. Failure to use adjusted age provides false results in regards to preterm baby’s growth percentiles. In some cases preterm babies are wrongly diagnosed as ‘failure to thrive’ simply because actual age rather than adjusted age was used.

Case study

Aryan was born at 24 weeks gestation weighing a tiny 460 grams. At the time of his birth he was also classified as intrauterine growth restricted (IUGR) for his gestational age. At 6 months actual age (2 months adjusted age) his mother, Rachel, contacted me for help to resolve Aryan’s aversion to bottle-feeding. She expressed concerns that Aryan has been classified as ‘failure to thrive’. When I plotted his measurements on an infant growth chart, his weight and length were both around the 7^th percentile, which was an increase since his birth. Aryan was thriving. I was perplexed as to why he had been diagnosed as ‘failure to thrive’. Anna informed me that his pediatrician had been using his actual age rather thanadjusted age. This mistake gave the false impression that Aryan’s weight and length were below the 1^st percentile, lower than at birth. Being incorrectly labeled as ‘failure to thrive’ was the reason Anna tried to force Aryan to eat more, which in turn caused him to develop an aversion to bottle-feeding.

8. Incorrectly labeling baby as ‘failure to thrive’

Failure to thrive (FTT) refers to failure to gain weight appropriately. The criteria typically used to diagnose FTT are as follows:

Weight-to-length or body mass index below the 5^th percentile curve on an appropriate infant growth chart.
Weight-for-age below the 5^th percentile or dropping 2 percentile curves on an appropriate infant growth chart.
Length-for-age below the 5^th percentile or dropping 2 percentile curves on an appropriate infant growth chart.

The problem with these criteria is that some healthy, thriving babies may be wrongly diagnosed as ‘failure to thrive’. For example:

Genetic short-statured babies born to short parents can be under the 5^th percentile for weight and length.
Constitutional growth delay babies can be below the 5^th percentile for weight and length.
Some genetically lean babies born to lean parents could be under the 5^th percentile for weight.
Babies experiencing catch-down growth can drop 2 or more percentile curves.
Preterm babies could be below the 5^th percentile if actual age rather than adjusted age is used.
Intrauterine growth restricted (IUGR) babies who are growing at healthy rate could be below the 5^th percentile for weight and/or length.

9. Assuming more food equals faster growth

If a baby is underweight, as is the case of a skinny IUGR baby or because a baby is underfeeding, more food mightimprove growth provided lack of nutrition is the reason baby is underweight. (See Poor growth for other reasons.) Genetically lean babies are underweight, but they’re not necessarily underfed babies. You can’t fatten a genetically lean baby.

If a baby already has a healthy layer of body fat, making him eat more than he is willing to eat by force-feeding might make him gain more body fat, provided it doesn’t cause him to develop a feeding aversion, which is likely. However, gaining more body fat on top of an already healthy layer of body fat won’t make him healthier, and it won’t make his length climb to higher percentiles on an infant growth chart any faster than if he were allowed to decide how much to eat. (See Petite baby for further explanation.)

10. Limiting the search for poor growth reasons to medical causes

The reasons for genuine poor growth can be grouped into two broad categories:

Organic - meaning there is an underlying physical causes. For example, acute or chronic illness, GERD, milk allergy or intolerance, metabolic conditions, congenital abnormalities, neurological impairment, or physical abnormalities affecting feeding ability.

Non-organic – meaning the cause is due to behavioral, environmental or social reasons. Examples include poverty, inappropriate or faulty feeding equipment, poor positioning while feeding, errors in preparing infant formula, chronic sleep deprivation, behavioral feeding aversion as a result of being pressured to feed, family violence, passive smoke and many more.

Studies show that 80 percent of babies who display poor growth have no identifiable underlying physical cause. [Source] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3195791/

And of the 20 percent who have an underlying physical condition that can negatively impact on growth, many also have an overlap of non-organic causes. If non-organic reasons are contributing factors then treatment of baby’s physical condition might not be enough to improve growth.

It is understandable that medically trained health professionals’ focus is on ruling out possible medical conditions because that it what they’re trained to do. However, what they often tend to overlook are the many behavioral, social and environmental reasons for feeding refusal and poor growth. No amount of medications or dietary changes will resolve feeding or growth problems related to non-organic causes.

It’s important if your baby has poor growth that your search for solutions is not limited search to medical causes.

Why you need to identify mistakes

When health professionals make mistakes they usually remain blissfully unaware. However, the mistakes they make can have serious consequences for babies and their families (see Consequence of baby growth mistakes) and so it’s important to your baby’s health that you are able to recognize if mistakes have been made.