Infant Growth: What EVERY Mother Needs to Know
A universal concern for new parents is whether their baby is getting the right amount of breastmilk/formula (henceforth referred to as "milk"). Because of conflicting information given to parents regarding infant feeding patterns and milk intake, parents may be relying on inaccurate or even dangerous information regarding their baby's feeding needs. On one extreme this can lead to overfeeding and set a child up for life long obesity, and on the other extreme it can lead to underfeeding and malnutrition. After seeing many parents caught off guard by their infants feeding problems, I've come to believe that it is vitally important for all parents to understand normal infant growth since this is the most accurate way to gauge if an infant is being adequately fed. My experience was recently validated by a study showing that when mothers are taught how to follow their baby's growth their breastfeeding practices improved, baby's weight improved, and they were more likely to breastfeed successfully.1
When a typical child is growing in a healthy environment and fed an appropriate amount of milk, they will follow a predictable pattern of growth.2 This does not mean that every baby will be the same size - far from it! As we all know, genetics are a major determiner of whether a person is of small or large stature. However, when researchers have followed the growth of thousands of children from all genetic backgrounds in optimal environments and they have found they all have a similar growth pattern.2 These patterns are what make up the data found in the WHO Growth Chart and the percentiles your pediatrician may inform you of at your child's well checks. For example, naturally smaller babies may hover around the 20th%, not varying dramatically up or down over the course of the year. Whereas a naturally bigger baby may hover around the 80th% throughout the first year. Both are considered healthy growth patterns since they maintained their percentile. Also note that growth charts work best after the first month, since birth weight may be influenced more by pregnancy related factors. (During the first month, a weight gain of 1 oz or more per day is normal, beginning on day 4 of life.*) Small, gradual shifts on growth charts are usually okay. A red flag for a feeding problem would be a baby whose percentiles are rapidly increasing or decreasing. If you notice this, immediately make an appointment with a lactation consultant or pediatrician to discuss your concerns.
Identify if Your Baby Could Be Underfed
While medical problems can cause poor growth patterns, if an otherwise healthy baby is dramatically swinging up or down in their weight percentiles it may be a clue that there is a feeding problem. Breastfeeding problems especially are best treated as soon as possible. If parents are tuned in to their baby's growth they can quickly seek out the support of a lactation consultant before a problem has gone on too long. The graph to the right is an example of baby whose growth should have raised red flags long before she came to see me at 7 months. The problem could have been identified much sooner, when her growth dropped off between 2 and 4 months. Notice how the red line representing her weight trends upwards in a nice curve from birth 2 months, but then begins to flatline, and her weight percentiles plunged from 97% to 1%. This baby was being seriously underfed, quite to the surprise of her parents who thought she was happy and thriving. If parents are equipped to monitor their baby's growth they can catch a problem early and get help from an expert on what changes need to be made. In this case, baby was not nursing nearly often enough to support a healthy milk supply.
Identify if Your Baby Could Be Overfed
In general, breastfed babies are really good at regulating their intake at the breast. Studies have found that breastfed babies feed slower than bottlefed babies and this helps them to sense fullness and switch to a non-nutrive suck that does not draw milk.3 One exception to this is when mother has oversupply and a very fast let down - the milk can flow so fast and furious that baby will rapidly swallow just to keep up. Bottle-fed babies, whether taking in breastmilk or formula, are prone to overfeeding.4 They are unable to comfort suck on a bottle like infants at the breast without drawing additional milk, so they may overfeed simply to satisfy their sucking needs. Because of the fast and effortless flow of bottles, they may drink the milk too quickly before they have a chance to register fullness. Caregivers also tend to encourage a baby to finish a bottle instead of looking for subtle cues the baby is full. Widespread false information exists on how much milk older babies should be taking in a bottle, leading to vast overfeeding of older babies. For this reason, its not a bad idea for parents to be on the look out for excessively rapid growth as well, since this may be a sign of overfeeding.4 Notice in the chart on the right how baby was small at birth (9%) but had a nice upward curve of the growth line to 2 months (19%) and then a rapid uptick in growth occurred launching the baby up to 40% at 4 months, 77% at 5 months, and 90% at 7 months. In this case, when mom went back to work the caregiver began overfeeding the baby at daycare. Instead of continuing small frequent feedings like breastfed babies maintain (example: 8 x 3.5 oz feedings per day) the caregiver was giving large 6-8 oz bottles. Once we caught the problem at 7 months, we were able to teach the caregiver paced bottlefeeding methods and gradually adopt a more healthy feeding pattern.
Boost Confidence In Your Milk Supply
Most new moms worry about their milk supply. It can be unsettling not being able to see and measure how much milk your baby is drinking at breast. There are several observational ways to watch for signs of a good milk supply (topic for a future blog post!), but the Gold Standard-No Question test of a good milk supply is to see your baby's growth steadily follow a curve on the growth chart and maintain approximately the same percentiles. Keeping an eye on your baby's weight percentiles is actually much easier than keeping track of how many ounces they are supposed to be gaining, since the rate of growth is constantly changing. For example, a 3 week old is expected to gain at least half a pound per week but a 5 month old is only expect to gain half pound every two weeks. Instead having to know the ever-changing rate of expected growth, simply monitor your baby's weight percentiles. You can be 100% confident that you a have a full, healthy milk supply and that your baby is feeding well if you see baby's growth line follow a steady curve and roughly maintain his percentiles (gradual shifts are usually okay, just not sudden or dramatic shifts). Notice how the baby on the right has a steady growth line that roughly follows a curve on the chart, and her percentiles don't vary widely. This baby is growing and thriving and mom can be confident in her milk supply.
Charting is Easy!
You can easily download a free app to chart your baby's growth. All you'll have to do is plug in your baby's weight at each checkup and the app will create the line and percentiles. Its very important to make sure you are using the World Health Organization (WHO) chart, not the CDC chart. The WHO chart was made based on data from thousands of healthy babies from around the world who were living and fed in healthy environment.5 As a result, the chart shows what normal healthy growth should look like. This is different than the CDC chart which was made with babies that were not growing in healthy conditions - so the percentiles really aren't helpful for identifying ideal growth.4 You learn more about the differences in charts here.
Get Help If Concerns Arise
If you have concerns about your baby's growth, its best to seek out the help of a feeding expert instead of making changes yourself. Sometimes its hard for parents to discern if a fluctuation is considered normal or alarming. A lactation specialist is trained in both breastfeeding and bottlefeeding, and can help you identify if your baby has normal feeding patterns, the condition of your milk supply, and what if anything needs to be changed. Your lactation consultant will also involve your baby's pediatrician to make sure that no other health conditions are contributing to growth problems.
* Weight Velocity, WHO, accessed 7/11/17
1 Using scores in interpreting growth status effectively improved infant feeding practices, Int. J. of Medical Science and Public Health, 2016
2 Creating the WHO Growth Standard for Infants and Young Children, CDC, accessed 1/19/17
3 Breastfeeding duration and its relation to weight gain, Appetite, 01/2017
4 Risk of Bottle-feedng for Rapid Weight Gain, JAMA, 05/2012
5 Comparing Methodologies, Growth Birth to 2 Years, CDC, accessed 1/19/17