Sometimes, babies who were doing very well and gaining weight very well
with exclusive breastfeeding start to gain more slowly and even not at
all after two to four months. Exclusively breastfed babies do tend to
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 is not the standard. Breastfeeding
is the normal, natural, physiologic way of feeding infants and young
children. Using the artificially fed baby as the model of normal is not
rational and leads us to make errors in advising mothers about feeding
In some 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
You can tell when a baby is getting milk and when he is not (see below
and the video clips at the website nbci.ca). 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
Why would your milk decrease?
This reason (number 11) requires more explanation. In the first few
weeks, babies tend to fall asleep at the breast when the flow of milk
slows down. This slowing of the flow occurs earlier in the feeding if
the baby is not latched on well. A baby who has a less-than-good latch
but whose mother has an abundant supply can gain well, but he really
depends on the milk ejection (letdown) reflex in order to get milk. The
baby will suck and sleep and suck, without getting large quantities
once the initial rapid flow diminishes but if the mother has more milk
ejection reflexes, he will drink some more, even half asleep. Once the
baby is older, however, some may pull away from the breast when the
flow slows down, often within minutes of starting the feeding (Actually
some do this from very early on, some never do this, and some do a
combination of sleeping and pulling away from the breast depending
probably on how hungry they are or their mood). This is more likely to
occur when babies have received bottles from early on, but can also
occur even without the baby’s having received bottles. When this
pulling occurs, most mothers will probably put the baby over to the
other side but then the same thing happens. The baby may still be
hungry and may refuse to take the breast again, preferring to suck his
hand. He won’t get those extra milk ejection reflexes (letdown
reflexes) that he would have gotten if he had stayed longer at the
breast. So, the baby drinks less and the supply also decreases because
he drinks less and the flow slows even earlier in the feeding (because
there is less milk) and a vicious circle has started. It doesn’t always
happen this way and many babies may gain weight well even if they do
spend only a short period of time on the breast. They may still pull
off the breast and suck their hands because they want more sucking
(which is pleasurable for them) but if their weight gain is good, there
is no need for concern. Still, it’s nice to have a baby breastfeed
without pulling at the breast.
- You have gone on the birth control pill, the
Mirena IUD, have received Depo Provera or are taking estrogens and/or
progesterones 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 don’t have to get up to feed him.
- 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 use results in the baby latching on less well and thus
getting milk less well from the breast. Often the baby will pull off
before he has “emptied” the breast, and 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 as
that is the same as a bottle) would be better than a bottle. See video
- An emotional shock can, occasionally, decrease the
- 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 doesn’t happen most of the time.
- Could you be doing too much? It is easy
to get caught up in trying to conform to others’ ideas of what you
should be doing. Let the housework go. Sleep when your baby sleeps. If
you are tired, lie down with the baby to breastfeed and let yourself
fall asleep. Make sure co-sleeping is done safely according to the
guidelines set out by UNICEF and UK Baby Friendly
- Some drugs may decrease your milk supply.
It is possible antihistamines do, especially the older ones such as
Benadryl; pseudoephedrine (Sudafed) can also decrease the milk supply.
Note that these two drugs (or similar ones) are found in cold and
- 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 getting 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 compression (see the
video clip and information sheet on compression at the website
nbci.ca.) 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? See the video clips at the
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,
- A combination of the above.
- Sometimes, the milk supply decreases for no obvious
reason. Well, maybe the reason is not so difficult to figure out as
that once you consider the information in the following paragraph and
know how to know a baby is getting milk from the breast (or not).
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 the Protocol to
Manage Breastmilk Intake and the video clips at the website
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 won’t work if you are pregnant and although there is
no evidence that it is worrisome to use during pregnancy, the absence
of studies showing concern does not mean it is safe during pregnancy.
How Do You Know The Baby Actually Drinks At The Breast?
When a baby is getting milk (he is not getting milk just because he has
the breast in his mouth and is making sucking movements), you will see
a pause at the point of his chin after he opens to the maximum and
before he closes his mouth, so that one suck is (open mouth
wide - pause - close mouth type of suck). If you wish to demonstrate this
to yourself, put your index or other finger in your mouth and suck as
if you were sucking on a straw. As you draw in, your chin drops and
stays down as long as you are drawing in. When you stop drawing in,
your chin comes back up. This pause that is visible at the baby’s chin
represents a mouthful of milk when the baby does it at the breast. The
longer the pause, the more the baby got. Once you know about the pause
you can cut through so much of the nonsense breastfeeding mothers are
being told. Such as: Feed the baby twenty minutes on each side. A baby
who does this type of sucking (with the pause) for twenty minutes
straight might not even take the second side. A baby who nibbles
(doesn’t drink) for 20 hours will come off the breast hungry. See the
video clips at the website nbci.ca which show when a baby is
getting milk (or not) and also how to latch a baby on and how to use
Questions? First look at the website nbci.ca or drjacknewman.com. If the information you need is not there, go to Contact Us and give us the information listed there in your email. Information is also available in Dr. Jack Newman’s Guide to Breastfeeding (called The Ultimate Breastfeeding Book of Answers in the USA); and/or our DVD, Dr. Jack Newman’s Visual Guide to Breastfeeding (available in French or with subtitles in Spanish, Portuguese and Italian); and/or The Latch Book and Other Keys to Breastfeeding Success; and/or L-eat Latch and Transfer Tool; and/or the GamePlan for Protecting and Supporting Breastfeeding in the First 24 Hours of Life and Beyond.
To make an appointment online with our clinic please visit www.nbci.ca. If you do not have easy access to email or internet, you may phone (416) 498-0002.
Slow Weight Gain After Early Good Weight Gain, 2009©
Written and revised (under other names) by Jack Newman, MD, FRCPC,
Revised by Jack Newman MD, FRCPC, IBCLC and Edith Kernerman IBCLC,