It’s a big question we get here at Formula Feeding Helpline: how much formula should I be letting my newborn eat?
I don’t pretend to know how – or when – the myth was created that the newborn stomach can only hold 5-7 ml of milk. And I don’t know why postpartum nurses have taken to hanging craft-like beads from their hospital-issued badges to conveniently illustrate that a newborn only need consume the visualized amount. It’s not grounded in science nor is it evidence-based.
(For clarification, I’m referring to babies on their first day of life and the next few days thereafter.)
Caregivers routinely reach out to us because they’re feeling a strong instinct that their baby can and should be eating more, but hospital staff, especially nurses, are very strongly directing them to hold back by instilling a fear of “overfeeding.”
Unraveling fact from fiction needs to begin with understanding what the science DOES tell us about newborn stomach size. When we look at the actual literature we find that newborn stomach size is actually about 20 ml, not 5-7 ml. In fact, the 5-7 ml myth was born out of a single study of just twelve mothers wherein their breast milk output was measured and newborn stomach size was never even assessed.
The following breakdown is from fedisbest.org:
However, using this 20 ml figure is only step one to understanding. The fact that 1) gastric emptying only takes about 1-hour to complete (the stomach empties), and 2) the stomach begins to expand rapidly after birth – means that a newborn can consume more than 20 ml right out of the womb.
But COLOSTRUM! It’s so fatty and rich and high in calories and carbohydrates that baby needs only drops of it in order to be sustained.
Yeah …you’ve been misled about that too.
Colostrum is unique in that it contains some passive immunity that mature breast milk does not, but other than that it’s rather lackluster when compared to its reputation.
Colostrum Per Ounce
|Formula Per Ounce|
The average formula fed newborn will consume about 12-16 ounces of formula in the first 24 hours of life. However, the average mother will only produce about 1 ounce (37 mls) of colostrum within the first 24 hours.
Notice that the above table is speaking in OUNCES. One ounce is equal to about 30 mls. Babies drink formula by the ounces, but most women do NOT produce colostrum by the ounces.
Because 8 out of 10 mothers choose to initiate breastfeeding after giving birth, we find that nurses have very little exposure to normal formula feeding newborn behavior and unfortunately regularly poorly advise.
While I never make sweeping generalizations about how much formula babies “should” eat, because it’s all so individualistic, I can tell you with decent certainty that babies born at or above 6.5 lbs all seem to start out life eating about the same amount: the first formula feeding after birth is about 30 ml or 1 ounce.
Often this feeding is given within one-hour of birth and I, personally, like to give it as soon as possible.
The second feeding, roughly 2 to 3 hours later, is also about 30 ml or 1 ounce.
By the third feeding this is often increasing to 40 to 50 ml (the stomach is already expanding).
And by 24 hours old, it is common for baby to be finishing 2 ounces (60 mls or a full nursette bottle).
After 24 hours of life consumption rates starts to vary more widely. Some babies are discharged from the hospital downing two 4 ounces a feeding (two nursette bottles). Some will hang on to the 2 ounce mark for a while longer or take longer to increase.
While the thousands of babies with which I have consulted are better evidence 😉 my own five children also serve to illustrate, so I’ll go anecdotal. My twins were born at 36 weeks weighing 5 lbs 12 oz and 6 lbs 5 oz. My second baby was born at 41 weeks weighing 9 lbs 1 oz. My fourth was born at 40 weeks weighing 8 lbs 15 oz. And my fifth was born at 40 weeks weighing 8 lbs 12 oz. Despite different gestational ages at birth, multiples vs singletons, and varying birth weights – they all followed the typical “first-24” pattern. The overwhelming majority of my clients do as well.
As always, our “how much and how often” rule applies to newborns too. That is, feed a baby until she stops. Burp frequently and offer her the bottle for up to 20 minutes. As soon as baby *consistently (a couple feedings in a row) and *efficiently (within 20 minutes) finishes a certain amount, up that amount by ½ ounce to 1 ounce.
BABIES CANNOT OVEREAT. They will stop feeding, turn their heads, or spit-up if they’ve taken in too much. Always let baby dictate feeds. Do not restrict feeding size.
In conclusion, 5 to 7 ml is NOT how much milk a newborn requires. They can and should consume more. The first newborn formula feeding is often 30 mls (or 1 ounce) and should be given readily. From there, increase feeding size as baby dictates with no regard for hypothetical stomach size or nurse scare tactics. Full babies are happy babies who will rest peacefully in between feedings. So happily feed your baby!
Questions about supplementing with formula until breast milk arrives? Worried about underfeeding? Want to combo feed from birth? Have you been discharged and wondering what to do now that you’re home? Contact us today!