The average breastfeeding baby consumes 19-30oz of breast milk per day.1 with the most common amount being 25oz per 24 hours.
Oddly one of the more curious practices that I’ve heard of is bottle feeding a breastfed baby to “make sure they’re getting enough”. Why is this odd? Because 19-30oz is a rather big range of difference. How do you know that your baby needs 19oz rather than 30oz? Or 30oz rather than 19oz? With bottles you know how many ounces your baby is getting but you do NOT know “how many ounces does my baby NEED?” With a bottle you can very easily under-feed a less demanding baby, or over-feed one that drinks too quickly.
With direct breastfeeding your breasts don’t have ounce markers, but baby has a very good indicator of “getting enough”. That indicator is that the baby cannot make sufficient output without sufficient input. The supply is regulated by the demand, and baby will generally change their nursing patterns to take in what they need and then comfort suck to avoid over-feeding. (There are rare exceptions to this rule if baby has severe reflux and mom has severe over-supply.)
Newborns will make one wet diaper per 24 hours of life. So in the first 24 hours your baby should make at least one wet diaper. In the second 24 hours the baby should make at least two wet diapers. This continues to day 6 or until mom’s milk comes in (whichever is first) at which point baby should begin making 6-8 wet diapers per day. In a newborn you want to make sure that the diaper count matches the day of life, and that the baby is passing meconium and transitioning to yellow breastmilk poops.
Infants will make 6-8 wet diapers per day, baby is getting enough in terms of ounces. A “wet” diaper is about 4 tablespoons of liquid, more than that is considered a “soaked” diaper which counts as two wets. A poopy diaper also counts as a wet diaper, and a poop + pee diaper is two wets. Watch for stronger more concentrated urine and “brick dust” in the diaper if you’re concerned about diaper counts.
Older babies slow down a bit on diaper production and tend to have more “soaked” and fewer “wet” diapers. In an older baby, especially a baby that has started solids, it tends to be a bit more important to look for other signs that baby is having problems with intake. Stronger concentrated urine is generally the first sign that something’s off. (Although if baby’s eaten a food like cabbage or asparagus their urine will be a lot stronger than usual.)
If baby’s wet diaper count is low, baby is not getting enough. The cause of this problem varies. Mom may not be recognizing baby’s feeding cues, baby may be lethargic due to jaundice or another health problem, mom may have a hormonal or physical issue that has not been properly diagnosed or treated, baby may have a physical issue such as a high palate or tongue tie, or there may be a milk transfer issue due to poor latch. If your baby’s not getting enough milk, seek help.
WEIGHT GAIN is separate from the issue of “is baby getting enough”. If baby is making enough wet diapers, baby is getting enough in amount. But there can still be issues that cause slower weight gain. A milk transfer issue, reflux, over-supply, hyperactive letdown, metabolic disorders, food sensitivities, a tongue tie, etc. can cause slower or low weight gain and even weight loss. This is NOT an issue of “low supply” when there are enough wet diapers. If you are being pushed to supplement for suspicions of “low supply” then you should look for the advice of a certified lactation consultant, preferably an IBCLC who can help you determine the cause of your baby’s weight issues. Many pediatricians or lesser certified lactation consultants will have a mom supplement when baby’s weight loss is being caused by OVERSUPPLY and when the weight issues could be easily resolved by block feeding and reducing mom’s supply.
Over-used and ineffective techniques to “measure mom’s supply” include:
- The “before and after a feed weigh-in”. This is ineffective because mom’s supply varies across the day. A morning feed often has the highest amount of milk, and evening feeds can result in very little intake. This is normal and healthy. Depending on when the weights are taken, mom may be at her high supply time or her low supply time. Baby may also be nursing less due to being in an unfamiliar environment, or mom’s letdown may be hampered by performance anxiety. Weights are an interesting bit of data but they have to be collected across 24+ hours in order for them to be meaningful.
- The “pump and see how many ounces you get” is one of the least meaningful tests of mom’s supply. As with the “before and after” weigh-ins, the amount mom will get varies across the day. Even worse, the amount mom can pump has nothing to do with how much a baby can get out of the breast or how healthy mom’s supply is. Pump output varies widely from mom to mom. I personally have very low pump output and can usually pump a half ounce from both breasts combined. A friend who had most of her milk ducts removed and who requires supplemental feeds can pump more than I can in a session but cannot make enough milk across 24 hours to feed her baby without supplementation.
- The “feed baby a bottle and see how much he will eat, and that’s how much he needs to get at every feeding” test is a terrible one, as babies easily over-eat from a bottle in a way that they would never eat from a breast.
- Physical indicators such as breast size, “engorgement” and leaking are not reliable indicators of mom’s supply. Supply regulation happens across mom’s nursing relationship and the faster her body stops leaking or becoming engorged, the better it is for mom’s and baby’s health.