Weight Gain

infant-baby-been-examined-on-the-balanceOne of the biggest concerns all new moms have is whether or not their baby is gaining enough weight, especially when they are breastfeeding. Moms go to their baby’s first few checkups holding their breath when their baby is put on the scale, waiting to see what the doctor’s verdict is. Is their baby in the 50th percentile or above?

Awesome…unless they are above the 90th percentile, in which case they must be gaining weight too fast, and are going to be overweight children and adults (and we know what a growing problem obesity is, especially in the US).

On the other hand, what if your baby is below the magical 50th percentile? Oh no…he must be starving. (Sarcasm intended)

So, what is a mom to do?

It’s important to remember that all the “percentiles” and statistics apply to the mythical “average” baby, who doesn’t exist in real life. Weight gain is only one measurement of growth, but doctors often tend to focus on the weight charts alone.

Here is what you need to keep in mind: When your baby is in the “50th percentile” for weight or length, it simply means  that half of the babies measured at that age weigh more than him (or are longer than him), and half weigh less (or are shorter).

Here are some guidelines that will give you an idea of what to expect as far as growth patterns in ‘normal’ breastfed babies.

  •  The ‘average’ baby weighs about 7 ½ lbs, and is about 20 inches long at birth. Remember, all that means is that half of all the babies born will weigh more than that, while half will weigh less. The average weight loss in the first few days after birth is usually 5-7% (about 7 or 8 ounces for the average baby), which means that when most babies come home from the hospital, they will weigh less than they did when they are born. This is your newborn’s baseline weight, and the one to use when you are calculating his weight gain, NOT his birth weight.
  •  In exclusively breastfed babies, milk intake increases quickly during the first few weeks of life, then stays about the same between one and six months – though it is likely to periodically increase during growth spurts. During the first six months, most babies will take in about the same amount  of milk:  around 25 ounces in 24 hours.
  •  At some point after six months, depending in how much of his nourishment comes from other foods,  your baby’s milk intake will gradually decline as his nutrient intake from other sources increases. The ‘average baby’ will ‘usually’ take from 2-4 ounces, but this varies greatly from baby to baby.
  • Most babies will double their birth weight by 4-5 months, and increase it by 2 ½ to 3 times by the time they are about a year old. Remember, these are only guidelines and don’t apply to each unique little person.
  •  Typical intake for an exclusively breastfed baby is 19-30  ounces per day. Average weight gain for first three months is 5-7 oz. per week. During the second six months, it averages 4-5 oz. per week, and from 6-12 months, it drops to between 2 – 4 oz. per week.
  • Research has shown that the growth patterns of breastfed and formula fed babies are not the same. Breastfed babies may grow faster than formula fed babies in the first few months, and then “slim down” compared to formula fed babies, especially between 6 and 12 months. However, there is a growing body of research to show that formula fed babies are actually MORE likely to become obese as children and adults than those who are breastfed.
  • Typically, breastfed babies who are “cue fed”, or fed ‘on demand’, as opposed to ‘on a schedule’, will regulate their own milk intake. Remember that it is best to learn your baby’s early signs of hunger, and not wait until he is stressed and crying before you feed him.  Crying is a late hunger cue. This series of photos will show you examples of a newborn’s feeding cues.

Formula fed babies are often encouraged to finish the “last little bit in the bottle” (after all, formula is EXPENSIVE), and they have such a strong need to suck (especially when they are newborns ), that they will often continue sucking as long as the artificial nipple is in their mouth, even after their tummies are full.

On the other hand, it is nearly impossible to make a breastfed baby nurse once he decides he has had enough. Breastfed babies must be actively sucking in order for the milk to flow strongly.  When they are nursing at the breast for comfort (non-nutritive sucking), as opposed to when they are really ‘hungry’, they are receiving only a trickle of milk. When they are very hungry, they nurse more vigorously, and receive a faster stream of milk. (See article Introducing Bottles and Pacifiers to a Breastfed Baby for more information.)

Many doctors aren’t aware of the new guide lines. When using the older growth charts (which are based on formula fed babies), they may think that a breastfed baby whose weight gain slows after the first few months is a red flag, and may recommend supplementing with formula. They may also express concern about babies who gain weight at a greater than average rate, especially during the first few months.

Babies who are breastfed may gain weight faster than those who are formula fed during the first 2 or 3 months. If a doctor goes by the old charts (based on formula fed who received solid foods earlier than today’s infants), and not on breastfed babies (who should be considered the ‘norm’), he may think that the formula fed baby’s excessive weight gain is normal, and not intervene to help them get to a healthier weight. This may lead to obesity later in life, and we know that obesity is one of the biggest health problems we have in this country.

The most important thing to remember is that breastfeeding is the biological norm, and baby’s weight should be evaluated based on that, rather than comparison to formula fed babies. Make sure your doctor is aware of the importance of using the new growth charts when he evaluates your baby’s weight. They give a much more accurate result than the old ones that were used for decades.

There are differences in growth patterns between breastfed and formula fed babies after the first 3 months as well:  From the 4th to the 12th month, breastfed babies tend to gain weight more slowly (even after solids) and are leaner at one year – breastfed babies consume 20% less milk than formula fed babies during this time, and their growth is perfectly normal.

During the first couple of weeks after your baby is born, while your milk supply is being established, it’s especially important to make sure that he is getting enough to eat. (See How Can If Tell if My Baby is Getting Enough Milk)

In evaluating a baby’s growth patterns, the following factors are equally as important as weight gain and  should be taken into consideration:

  • Length : For the first 6 months, the ‘average’ baby grows approximately1 inch per month, and from 6-12 months, they grow 1/2 inch each month.
  • Head circumference: 1/2 inch per month for the first 6 months, and 1/4 inch per month during months 6-12.
  • Family history: A child who comes from a family of very short people is, in all likelihood, going to also be on the short side, and a child that comes from a family of tall, thin people will probably be tall and thin.
  • Development: Is the baby happy and meeting developmental milestones appropriately?

Your health care provider should look at all of these factors when evaluating your baby’s growth, not just how many ounces he gained in a given month, or what percentile he is on the weight charts.

If your health care provider considers all these factors and determines that there is a genuine reason to be concerned about your baby’s weight gain, this article will give you detailed information on how boost your milk production: Increasing Your Milk Supply. If he tells you that your exclusively breastfed baby is overweight, or is ‘too fat’, then it may be time to get a second opinion, or possibly, look for another who is more knowledgeable about and supportive of breastfeeding.

I have had two babies out of six who didn’t gain weight the way all the charts and the doctors said that they should. They both started out at the 95th percentile at birth, and ended up at the 10th during the second half of their first year. I tried everything to get them to eat, and they still stayed on the low, low end of the charts. They are both very healthy and intelligent adults now, but one is thin and can eat anything without gaining weight, and the other is what would be considered ‘average’, and her weight fluctuates within normal range according to her activity level and food intake.

I believe that to a degree, babies are genetically ‘programmed’ to be on the thin or the heavy side, according to family history. My six kids have two different dads. All were exclusively breastfed until around the middle of the first year of life, and I practiced cue feeding and baby led weaning with all of them. I wish I had figured out that there was only so much control I had over their weight when they were babies. I could have saved myself a lot of worry, because I stressed way too much about their weight gain during the first year, and tried my hardest  to force feed them, which never, ever worked.

In my experience, a healthy baby who is fed breast milk on demand, as well as offered a variety of nutritious foods once he starts solids,  is going to be just fine. He may not follow the pattern of the “average” baby exactly, but then you have to remember that the average baby simply doesn’t exist in real life.

None of my six babies were “average”…is yours?

References: WHO Growth Standards  (Recommended for Use in the U.S. for Infants and Children 0 to 2 Years of Age)

The World Health Organization (WHO) released a new international growth standard statistical distribution in 2006, which describes the growth of children ages 0 to 59 months living in environments believed to support what WHO researchers view as optimal growth of children in six countries throughout the world, including the U.S. The distribution shows how infants and young children grow under these conditions, rather than how they do grow in environments that may not support optimal growth.

The CDC recommends that health care providers:

  • Use the WHO growth standards (revised in 2006) to monitor growth for infants and children ages 0 to 2 years of age in the U.S.
  • Use the CDC growth charts to monitor growth for children age 2 years and older in the U.S.

Not all doctors are aware of the updated charts. If they are not using the revised and more accurate information, share these links with them:  http://www.cdc.gov/growthcharts  and http://kellymom.com/bf/normal/weight-gain/.

Anne Smith, IBCLC
Breastfeeding Basics

(Edited December, 2015)

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FBAR Sepia baby with dog 2013


Anne Smith, IBCLC
Breastfeeding Basics

About Anne Smith, IBCLC

Anne Smith, IBCLC
As the mother of six wonderful breastfed children, three perfect breastfed grand babies, and an IBCLC (International Board Certified Lactation Consultant) with over twenty-five years experience in lactation counseling, I can offer you professional support, as well as information and advice based on my personal experiences over the years.

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