Late Onset Decreased Milk Supply or Flow

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More and more frequently we are starting to hear about exclusively breastfed babies who were doing very well and gaining weight very well. Then, these babies begin to pull at the breast, fuss at the breast. Sometimes the babies start to gain more slowly and sometimes not even not at all after two to four months of age.


Exclusively breastfed babies do normally gain more slowly after three or four months compared to artificially (formula) fed babies, but this is normal. The more rapid weight gain of the artificially fed baby should not be the standard. Breastfeeding is the normal, natural, physiologic way of feeding infants and young children. Using the artificially fed baby as the standard of normal is not rational and leads us to make errors in advising mothers about feeding and growth.


Sometimes the baby starts to act as if something is not right


In some unusual cases, however, an illness in the baby may result in slower than expected weight gain. Supplementing with formula does not cure the illness and may rob the baby of the beneficial effects of exclusive breastfeeding.


You can tell when a baby is getting milk well from the breast and when s/he is not and when the drinking could be described as borderline. If the baby is sucking at the breast and not getting milk, well, this explains why he is not gaining weight and it is most likely the mother’s milk supply is down. The mother’s milk having decreased is the most common reason that the baby fusses and pulls at the breast and/or no longer gains weight well enough.




  • You have gone on the birth control pill, the Mirena IUD, have received Depo Provera or are taking estrogens and/or progesterone in another way. It should be noted that breastfeeding itself has a significant contraceptive effect, especially if you are breastfeeding exclusively.


  • You are pregnant. Pregnancy definitely decreases the milk supply


  •  You have been trying to stretch out the feedings or “train” the baby to sleep through the night. If this is the case, feed the baby when he is hungry or sucking his hand. Consider safe co-sleeping so the baby feeds at night and you do not have to get up to feed him. “Sleep training” is a common cause of late onset decreasing milk supply and flow. Many babies get a significant amount of their milk during the night.


  •  You are using bottles more than occasionally. It is better to avoid bottles altogether, but the occasional bottle is not usually going to influence your milk supply. However, regular, frequent bottle, even one bottle a day every day, results in the baby latching on less well and thus getting milk less well from the breast. Tongue ties, by definition result in a less than ideal latch.


  • Often the baby will pull off before the breast has “emptied” due to slower flow, with the result that the milk supply decreases. See below under “This reason requires more explanation”. If you must have the baby fed by someone other than you, then a cup (not a sippy cup which is essentially a bottle) would be better than a bottle. Watch this video cup feeding. The baby is 4 months old in this video..


  • An emotional shock can, occasionally, decrease the milk supply (maybe). This does not happen often if at all and the notion should not be overly emphasized. Too often mothers are told that their milk supply is low because they are nervous, lacking confidence or had a traumatic event in their lives.


  • Sometimes an illness in the mother, particularly if the illness is associated with fever, can decrease the milk supply. Mastitis and blocked ducts can also decrease milk supply. Fortunately this does not happen most of the time.



  • Some drugs may decrease your milk supply. It is likely that antihistamines, particularly the older ones such as diphenhydramine (Benadryl) do,; Pseudoephedrine (Sudafed) can also decrease the milk supply apparently, but it is usually taken, combined with diphenhydramine, so one cannot say for sure. Note that these two drugs (or similar ones) are found in over the counter cold and allergy medicines.


  • You are feeding one side only at each feeding. It is not a good idea to feed the baby on just one side, to follow a rule. Yes, making sure the baby “finishes” the first side before offering the second can help treat poor weight gain or colic in the baby, but rules and breastfeeding do not go together well.


If the baby is not drinking, actually drinking milk, there is no point in just keeping the baby sucking without getting any milk for long periods of time. You should “finish” one side and if the baby wants more, offer the other. How do you know the baby is “finished” the first side? Because the baby is no longer drinking, even with breast compression. This does not mean you must take the baby off the breast as soon as the baby doesn’t drink at all for a minute or two (you may get another milk ejection reflex or letdown reflex, so give it a little time), but if it is obvious the baby is not drinking, take the baby off the breast and if the baby wants more, offer the other side. How do you know the baby is drinking or not? You can tell when a baby is drinking milk and when s/he is not and when the drinking could be described as borderline.


If the baby lets go of the breast on his own, does it mean that the baby has “finished” that side? Not necessarily. Babies often let go of the breast when the flow of milk slows, or sometimes when the mother gets a milk ejection reflex and the baby, surprised by the sudden rapid flow, pulls off. Try him again on that side if he wants more, but if the baby is obviously not drinking even with compression, switch sides.


  • A combination of the above.


But the most common cause is that the baby’s latch is not as good as it can be.  And why would that be?


Because of


1. “Technique” of positioning and latching the baby on


Click the chapter from my book What is a good latch


2. Use of artificial nipples such as bottles and nipple shields and


3. The baby has a tongue tieSome tongue ties are obvious, but many tongue ties are more subtle and require an evaluation that goes farther than just looking, but includes feeling under the baby’s tongue as well and knowing what to feel for.  Unfortunately, few health professionals, including lactation consultants, know how to evaluate whether or not the baby has a tongue tie.  This is particularly true for physicians in general and pediatricians in particular.


4. The mother has had a decrease in her milk supply.  Late onset decreased milk supply is common. And when the milk flow slows, the baby tends to slip down on the nipple and the latch is even worse, so that decreased milk supply itself can lead to more decrease. For more information on late onset decreased milk supply and what can be done. See also Really good drinking with English textNibbling, 12 day old, English text“Borderline” drinking with English textfor video clips showing babies drinking well at the breast, or not.  Watch the videos, read the texts and then watch the videos again.  Following the Protocol manage BM intake may change things so he does gain well.


The way to prevent this all is to get a good latch from the beginning. Many mothers are told the latch is perfect when, in fact, it is far from perfect. The latch can still be improved even in the older baby, but it’s not always easy. But sometimes it is. See also the Protocol to Manage Breastmilk Intake


Often, domperidone will increase the milk supply significantly and we use it often. However, you should not use it if you are pregnant. In the first place it will not work if you are pregnant and although there is no evidence that it is worrisome to use during pregnancy, the absence of studies showing no concern does not mean it is safe during pregnancy.


We start domperidone with 30 mg (3 tablets) 3 times a day and sometimes go up from there in two steps, first to 40 mg (4 tablets) 3 times a day and then 40 mg (4 tablets) 4 times a day, or 50 mg (5 tablets) 3 times a day (for convenience).


See protocol to manage breastmilk intake on this website. If your doctor is reluctant, show him her this article and this article as well as this article (from the New Zealand Medical Journal Vol 128 | No 1416 | 12 June 2015) and show these to your doctor. Google “How to get domperidone in the US” and you should get websites that can provide domperidone.




You can tell when a baby is getting milk and when he is not and when the drinking could be described as borderline.


The information presented here is general and not a substitute for personalized treatment from an International Board Certified Lactation Consultant (IBCLC) or other qualified medical professionals.


This information sheet may be copied and distributed without further permission on the condition that you credit International Breastfeeding Centre it is not used in any context that violates the WHO International Code on the Marketing of Breastmilk Substitutes (1981) and subsequent World Health Assembly resolutions. If you don’t know what this means, please email us to ask!


©IBC, updated July 2009, June 2017, 2021


Questions or concerns?  Email Dr. Jack Newman (read the page carefully, and answer the listed questions).


Make an appointment at the Newman Breastfeeding Clinic.