How to Tell If You Have a Low Milk Supply — Top 4 Ways

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Let’s first define what a low milk supply is because we sometimes have moms have what’s called “perceived low milk supply” and that is when they think they aren’t producing enough milk but in reality they are. This can be because of the misconstrued messages and images that you see on in the internet or by talking to your friends. There’s this pressure to have a freezer stash of milk and this notion we have to have an abundance of milk on hand when that isn’t actually the case.

What is low milk supply exactly?

Low milk supply is when a mom cannot exclusively breastfeed her baby based on the milk she is producing within a 24 hour window in order to sustain his or her growth. As a result, he or she may be at risk of malnourishment or be diagnosed as failure to thrive. In summary, it is when we don’t see consistent and healthy growth for the baby based off of just breast milk alone because he or she is not getting enough of it.

I want to stress that the definition does not include a set number of ounces. This is because there are some variables such as your baby’s gender, size, gestational age at delivery, and even the composition of your milk that can all play a role in how many ounces your baby needs. If you are looking for an average number, a general rule of thumb is about 25 ounces for a full-term baby about three or four weeks of age and on in a 24 hour period until solid foods are introduced.

Poop tells it all

The two main ways to measure if your baby is growing appropriately are diaper output and weight gain. Diaper output is probably the easiest method for parents to measure at home because it can be easily tracked. Both the quantity of wet and dirty diapers increase after birth up to a certain point and then will plateau for an extended period of time. For dirty diapers the coloring of the poop should also change in the first few days.

It’s also important to note that the quantity of dirty diapers are actually more important and a better indicator of growth and milk consumption than the number of wet diapers produced in a 24 hour period. It is possible to have enough wet diapers but not enough poop so it is important to be tracking both.

The number of wet and dirty diapers varies depending on how old your baby is. I do have available a free chart that summarizes the minimum quantity of diapers you want your baby to have within a 24 hour period. If you would like to reference it, you can get a copy of this free resource here.

What’s considered a “full” diaper?

Now some parents struggle with identifying what is considered a “full” wet or dirty diaper. To assess what a wet diaper should feel like, take a clean, fresh diaper that hasn’t been used. Next, pour about three to four tablespoons of water into the diaper. Those three to four tablespoons would be essentially the saturation we are looking for when you can count it to be one “full” wet diaper. A common mistake is assuming that any amount of urine in the diaper is counted as one full diaper but that’s not enough. For dirty diapers, you want the poop to be about the size of a quarter and that would count as one “full” dirty diaper. By tracking both wet and dirty diapers, especially in the first few weeks of life, you can make sure that your baby is growing and getting enough input based off of his or her output.

Weight gain: following a healthy trend

The next indicator you should be measuring is weight gain. This is probably the best out of the two common ways to assess if your baby is growing as expected. Weight gain also varies by age. Generally speaking, from when your baby is born, it is normal for him or her to lose a little bit of weight in the first two weeks, but this weight loss shouldn’t be more than 10% of his or her birth weight. If it is more than 10%, then most providers will say that you need to be supplementing. This may be temporary or it may be something you have to continue doing if your milk supply doesn’t increase to where it needs to be in order to exclusively breastfeed.

At two weeks old your baby should be back to his or her original birth weight. However, after that two week mark and till about three months of age, we are looking for about one ounce of weight gain per day of life. There is variance to this rule of thumb as well, and this is gonna depend on your child’s weight percentile on growth charts, whether your baby was full-term or pre-mature, gender and more.

Is this something you should be tracking?

Most first time moms don’t need to be obsessive over your baby’s daily weight gain. As previously mentioned, one ounce a day is a good rule of thumb but it is not a realistic daily expectation because weight gain will always have fluctuation. The overall trend of his or her weight gain matters more than a daily weigh in on a scale.

However, it may gives some moms peace of mind to do a daily weigh in. If that’s the case, the Greater Goods Smart Baby Scale (pictured above) is my favorite at-home scale that is fairly accurate for tracking consistent weight gain. It isn’t as precise of a scale as you would find at a lactation consultant’s office or at your pediatrician’s office, but it is something that you can have in your own home if you want to weigh your baby every few days. This scale is accurate to 10 grams, the equivalent to .1 ounce.

Ever heard of a test feed?

The most guaranteed way to measure a baby’s intake of milk is by doing test feeds, also known as weighted feeds, because they are the most precise method. These feeds are done using an extremely accurate scale that the average person will not have available in their home, and I do not recommend you buy one just for this short period of time because they are expensive. Although, they are some retailers that will rent them for a much more reasonable price if you are interested.

You can find these types of scales with some lactation consultants or sometimes your pediatrician office. Any office that works with babies, such as a pediatric chiropractor, may have this as well. The scale that you will want to use for these type of feeds are accurate to two grams which means if something is weighed using that scale, it is accurate within a margin of error by no more than two grams. It’s very precise and it is designed for this type of use.

How to do a test feed the right way

To perform a test feed you will weigh the baby before you prior to the start of a feed. Some healthcare professionals will want to do a naked weight while others may ask you to have your baby dressed down to just the diaper. You could even do this with your baby fully clothed but what matters the most is that he or she is dressed consistently at both the start and end of the test feed. Once your baby’s weight has been taken and recorded you will feed him or her on one breast. Another weigh in will be taken and recorded before feeding your baby on the other breast. You will end the test feed by doing one last weight in after your baby has nursed from both sides.

The difference in weight is the amount of milk they consumed in grams. This is why it is so important that your baby is weighed while being dressed exactly the same at the start of the feed. One gram is equivalent to approximately one milliliter of breast milk, and we know 30 milliliters is equivalent to one ounce of breast milk. So this is a really great way to measure how many ounces/milliliters your baby is getting of your milk. Even though it is just one feed, it’s a good average and it gives you an idea of where your supply is at.

If you have eight feeds in a 24 hour period, you would then multiply eight times whatever that amount was from that feed. This will give you a rough estimate of how much your baby is consuming and this is helpful when comparing this to the 25 ounces a baby is consuming in a 24 hour period at three to four weeks old

Who really needs to worry about test feeds?

This is my favorite way to assess intake but, I know not everybody has access to do a test feed and that’s why diaper output and weight gain are standard measures that work just as well. Test feeds are definitely something I would encourage if you are facing chronic low milk supply or have had a history of low supply and you need further assurance if your baby is getting enough at the breast.

If you are doing weekly test feeds and/or weight checks then you may not need to invest in your own at home scale because once a week is typically sufficient to monitor progress and trajectory. You are totally welcome to get a scale if it gives you the peace of mind like I mentioned previously but, it even less necessary if you are doing test feeds on a regular basis.

Can you really rely on your baby’s demeanor?

The last way to assess your supply is by monitoring your baby’s temperament. This can also vary, and while by no means is this an exclusive indicator, it can give you supporting evidence as to whether or not you are facing a supply issue. For example, if your baby is generally content, sleeping well, and has a satisfied demeanor then it may be assumed that your bay is having all of their needs met, including nutritionally. The opposite may be true if your baby is fussy, showing hunger cues, and is showing clear signs of distress, then you may wonder if you have enough milk.

The tricky thing about temperament

However, it is equally true if your baby is jaundiced and he or she is really sleepy at the breast (this is a common symptom), then this can be confused with your baby being so full and satisfied that he or she is now ready for a nap. In this instance, this would not be the case.

The likely reality is your baby might be too tired or fatigued to continue feeding. and so what we really want to use in order to properly deduce the problem at hand are these other factors: diaper output, weight gain, and test feeds. Those are going to be way better indicators if your baby is getting enough than solely watching your baby’s cues and temperament. Your baby’s cues are also important, but I do want to stress that that is only one piece of the equation you need to take into consideration, and it is the least reliable.

Temperament may also suggest something else may be wrong. If all else is measuring up and your baby is growing healthily but their temperament is questionable, then I’d recommend seeking out help from your pediatrician or lactation professional to rule out other concerns beyond milk supply, and if needed, seek out a second opinion.

Again, temperament is a supplemental bit of evidence, it is not an exclusive indicator, so do not rely on it solely.

Don’t forget to use charts to check your progress

Don’t forget to download my free resource that summarizes all of these points, but most importantly, includes the chart for diaper output you should be using as a reference. Making sure your baby is growing and thriving shouldn’t be so hard, so make sure to take advantage of that PDF!