After your breast milk has been in the refrigerator for awhile, you may have noticed that it separates, with the fattier milk rising to the top. This breast milk fat separation is totally normal and nothing to be concerned about. However, some women worry that they aren’t making enough of the fatty milk, and that they have something called a foremilk/hindmilk imbalance that is hurting their baby. Here’s how to know if this might be an issue for you, and how to fix it if you’re pumping.
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What is foremilk and what is hindmilk?
Foremilk is the milk that flows out of your breasts at the beginning of a pumping session, while hindmilk is the milk from the end of a session.
What is the difference between the two? Because the fatty parts of breast milk stick together, and to the sides of your milk ducts, the milk that is released from your breasts first contains less fat and is more watery. Later, when the breast is more empty, more and more fat begins move out of the ducts and flow out of the breast.
Therefore, foremilk tends to have less fat than hindmilk, as the amount of fat in breast milk will gradually increase during a pumping session.
What is foremilk/hindmilk imbalance?
Foremilk/hindmilk imbalance can occur when a baby fills up pretty much exclusively on foremilk and doesn’t get much of the fatty hindmilk when he eats. This can result in the baby taking in too much lactose and not enough fat.
What are the causes of foremilk/hindmilk imbalance?
In babies that nurse, this can happen if the mother has an oversupply or if the baby is frequently switching breasts during a nursing session. When this happens, baby becomes full from the foremilk and stops eating, so she doesn’t get hindmilk from either breast.
This happens less frequently with exclusive pumpers, because you are feeding your baby a bottle with all of the foremilk and hindmilk mixed together, rather than foremilk first followed by hindmilk. However, some exclusive pumpers may also struggle with this if they have an oversupply or if their pumping sessions are on the shorter side.
What are some common foremilk/hindmilk imbalance symptoms?
Your baby getting too much foremilk and not enough hindmilk may result in the following symptoms:
- Becoming more fussy than normal
- Having colic symptoms
- Becoming gassy
- Having green poop
When should you be concerned about an imbalance?
First, I wanted to note that many lactation consultants agree that foremilk/hindmilk imbalance is not very common. (This is a great piece on the subject.)
Parents often worry when they see that their baby has a green stool. However, foremilk/hindmilk imbalance isn’t the only cause of green stools: green poop can be the result of something you ate (green vegetables or something with food coloring), teething, a virus, or starting solids, for example.
My suggestion is to not be too anxious about green poop unless your baby’s poop is consistently green and he is very fussy. However, if this is the case – most dirty diapers are green over a day or two (and possibly “frothy“) and your baby is not a happy camper, there are some things you can do to try to fix it. (Note: You should call your pediatrician regarding any health concerns that you have for your baby.)
Because there has been some confusion in the past, please note that this is NOT necessarily an example of foremilk/hindmilk imbalance; it’s just showing the breast milk fat separation. You can’t tell if there is “enough” hindmilk from looking at a photo, unfortunately.
What should you do if you’re exclusively pumping and think foremilk/hindmilk imbalance may be an issue?
There are a few things that you can try.
- Pump for longer. If you are concerned that the milk you’re pumping doesn’t have enough hindmilk, one way to increase it is to pump for longer so that you’re pumping when your breasts are emptier. (Remember, the emptier the breast, the fattier the breast milk.) So, you could try adding a few minutes to each session, or you could drop a session so that that you’re pumping less time but for longer. For example, if you’re doing 8 pumping sessions that are 15 minutes long, you could change your schedule so that you’re pumping 7 times per day for 20 minutes, and see if that helps. Also, you can try some strategies to empty your breasts faster.
- Separate out the first ounce. If you have an extreme oversupply (say, you’re pumping over 50-60 ounces per day), and you think you are pumping too much watery milk, you can bring a separate container with you when you sit down to pump. After you pump the first ounce, disconnect your bottles and pour the milk into the separate container. Then, reattach and keep pumping.
- Keep milk from pumping sessions together. If you are not an oversupplier, you might want to try keeping the milk that you pump from one session into one single bottle (and make sure that session is long enough that you’re getting hindmilk). This way, if you pump until you’re fairly empty, you know that you’re combined the foremilk and hindmilk from one session into the one feeding, and it should hopefully have the right amounts. It’s sort of like block feeding for pumping.
- Mix all your milk together. Yes, this is the opposite of what I just said! Different things will work for different people, and some oversuppliers find that using the pitcher method (where you put all of the milk you pump into a pitcher and then prep bottles from that) helps them manage issues with foremilk/hindmilk imbalance. This can be especially helpful if you pump into more than one bottle on a side at some pumping sessions.
Common Foremilk/Hindmilk Imbalance Questions
Here are a few additional common questions.
Should you throw away extra foremilk?
If you decide to separate out of the first ounce or so that you pump as described in the second option above, should you throw it away?
No! Just because it’s watery doesn’t mean it’s any less liquid gold. Some things you can do with it include:
- Mix it your baby’s solid food (if she hasn’t started solids yet, you can freeze it until then)
- Use it in a milk bath
- Make breastmilk jewelry from it
- Make breastmilk lotion or breastmilk soap, etc.
I feel like there is not a big enough layer of fat at the top of my refrigerated bottles. How big should it be?
There is no “correct” amount of separation. The only way to see if there is an imbalance issue is to look at your baby, not your breastmilk.
Is she gaining weight appropriately? Is she mostly happy? Are her poops mostly not green? If these are true, then don’t worry about what the breast milk fat separation looks like the in the fridge.
How can I tell if my issue is foremilk/hindmilk imbalance or dairy allergy?
Because the symptoms are very similar, it can be hard to know which is causing your baby to be unhappy.
I would try fixing one of the two issues at a time. You can try cutting out dairy and see if that helps. Or, you can try to correct the possible foremilk/hindmilk issue (by using one of the four options listed above, if you’re an exclusive pumper, or by block feeding, if you’re nursing).
The reason I wouldn’t do both at once is that if and when things improve, you won’t know which change did it and what the underlying issue was, and you might be stuck on a dairy free diet when it’s not necessary. (However, if you’re desperate for things to improve, then do what you have to do!)
Have you dealt with foremilk/hindmilk imbalance? Or been worried about green poop? Tell us about it!
References- Bonyata, Kelly, IBCLC. “Foremilk and hindmilk – what does this mean?” https://kellymom.com/bf/got-milk/basics/foremilk-hindmilk/
- Breastfeeding Problems. “Foremilk Hindmilk Imbalance.” https://www.breastfeeding-problems.com/foremilk-hindmilk-imbalance.html
- Kellymom. “Mother-2-Mother Concerns: Green Stools.” https://kellymom.com/mother2mother/m2m-green-stools/
- Madden, Katie, RN, IBCLC. “‘The Good Milk’ Foremilk/Hindmilk.” https://balancedbreastfeeding.com/the-good-milk-foremilkhindmilk/
I read this page and still don’t feel like I know how to tell if I have an imbalance by looking at a bottle or pitcher in the refrigerator. It would be very helpful to have some pictures of what’s normal and what’s an imbalance.
Hi Ashley! The issue is that it’s very difficult/impossible to tell from a picture or even just from looking at your milk. If you have a very thin (or no) layer of fat on top of your milk after a full pumping session and your baby has green poop and is very fussy, there may be an issue. I wish I could be more helpful!
So on this post, there are two pictures. Is one of them an example of an imbalance? I feel like my milk has three layers. In a 4 ounce bottle, there is 1/4 inch of a very translucent layer at the bottom, then about 2 inches of a more creamy white layer, then a layer on top of fat that is about 1/8 inch.
I guess I’m just trying to figure out if my little one has an intolerance to something in my diet or do I have an imbalance. I generally pump 30 minutes every session and then combine in a pitcher before making bottles.
No, neither is meant to be an example of an imbalance. Sorry if that is confusing. They are meant to show the difference between hindmilk and foremilk.
To me it doesn’t sounds like an issue with an imbalance based on what you’ve said. Do you feel pretty empty at the end of your sessions. How many letdowns do you usually get?
Hi! i’ve noticed that my baby has been fussy lately mostly at night. I give her gas drops which seem to help. i exclusively pump and i’ve noticed i don’t get much fat in the bottle from what i pump. i pump anywhere from 8-9 times a day for at least 15 minutes at a time. My baby has also had some stinky green poop lately as well as some super loose poops. (almost like diarrhea with no seeds) I’m worried i might have an imbalance as i’ve cut diary out of my diet since she was born because i have a dairy problem as well. She’s only had a handful of bottles of formula since birth but i’m really beginning to notice this problem and i’ve only been pumping for 3 weeks now.
Hi Lexie! Maybe you could try doing 7-8 sessions that are 20 minutes long and see if that helps you get more hindmilk?
My little boy is almost six months old and I’m trying to slowly stop pumping. I’ve noticed since I’ve drastically cut my pumping sessions, I’ve noticed there is now only a thin layer of fat after being in the refrigerator. Is it worth giving it him the milk with little to no fat My son has had issues with gaining weight since he was born. I’m an emotional mess because I’ve tried introducing formula, but he will not take it from me. Any help would be greatly appreciated.
Hi Nadia! I would try mixing the breast milk you pump with formula – if you slowly increase it (start with just a splash), he might get used to the taste. Having formula in the bottle will also help if there happens to be too much foremilk. Hope that helps!
Hi!
Thank you for providing such helpful info! I was wondering, is it possible to have an imbalance without having an oversupply? I am currently pumping with a few nursing sessions during the day. I only manage to pump what he eats in a day so I don’t believe I have an oversupply. When I pump I only have a very thin layer of fat at the top (pumping for 20-25 min with hand expression).
Baby has been having watery green poops for a couple weeks now with a decent bit of gas. I’ve been to the doctor and stopped eating dairy/soy incase it’s caused by a sensitivity to that, but nothing is helping.
Hi Rita! I do think it’s possible without an oversupply. How many times a day are you pumping?
Hello,
My baby is very fussy/cholic. Her nappies have been grassy green the past day.
I produce a lot of milk, it goes all over the place, my daughter pulls her head back off my breast only minutes after starting a feed then cries and I struggle to get her to re latch and often she will only latch on the other breast visa versa.
She has a lot of wind, I’m doing my best to keep her upright after a feed and winding her.
she strains a lot before eventually passing wind, goes red in the face and is in obvious discomfort.
I took her for her 6 week check yesterday and the dr diagnosed an umbilical hernia, probably from draining to pass wind.
Could there be an imbalance?
Hi Bev! Congrats on your new baby! If she is switching breasts early on, I do think that could be an issue with an imbalance. I am not an expert in nursing, though, so you might want to see a lactation consultant for help!
My little one is 5 weeks old and I EP and top off with a bit of formula as my supply is low. His poop for the past few days has been green and watery and he is a bit fussy. I’m suspecting I have a case of milk imbalance. My milk separate as the image above. With 80% of the bottle being foremilk and 20% being thicker hindmilk. I am pumping 8 times a day, 15-20 each session. What can I do to regulate the ratio better??
Hi Nora! I think that is actually a pretty good ratio. Is it possible that he has a virus instead?
In the picture above, is that a good ratio? Should the foremilk/hindmilk be 50/50? Are there any good to eat that make more fattier milk or is it all really only related to how long/often you pump? Thank you for your dedication to the subject! You are helping so many, including myself!
Thanks so much Casey! That is probably a larger ratio than I have usually had. Just a small layer of fat is fine (and so is this)! I have heard that some foods can increase breastmilk fat but I don’t know that it’s supported by research (and the empty breast is). It wouldn’t hurt to try it! I hope that helps!
My boy is 5 weeks old and nursed for the first 3ish weeks but now I exclusively pump. His last couple of poops have been yellow but frothy/mucus-y. Is this a foremilk/hindmilk imbalance or maybe an allergy? He also drinks a few ounces of formula each day because I don’t produce enough just pumping. He’s very fussy and gassy and only poops once a day after massage and bicycle kicks and occasionally rectal stimulation.
I think it could be either an imbalance or an allergy – I’m so sorry I can’t answer this better. Do you notice a layer of fat on your refrigerated bottles? And how often do you pump and for how long?
Hi, I have a 6wk old and am EP. I pump about 5-6 times a day at 30mins each. I always see maybe about a half inch of hindmilk fatty layer on top and the rest is the foremilk! How can I resolve this? Also if I try to pump for longer sessions, say 40mins, will this mean my next pump session will have more hindmilk and less foremilk? I’m a bit confused as to why breasts should be fully empty- does this decrease foremilk in the sessions after?
Also, forgot to add, that I am already dumping the first few minutes of foremilk- the clear thin blue tinted milk. I always get at least 2oz of it from each breast!
Hi Jay! Congrats on your 6 week old! Is your baby having symptoms of imbalance? I just want to get the full picture.
Thank you!!! I noticed that she started getting greenish poop diapers yesterday…not so much frothy but they definitely look like avocado color…I have not eaten anything green recently. She does get gassy as well. Otherwise she is ok.
My son is 5 days old, I exclusively pumped every two hours for 20-30 minutes but decided that the exclusively pumping life isn’t ideal with a 2 year old so I tried to get my son to latch and he successfully does! But, I am producing way too much milk. Do I need to worry about losing my milk completely now that I’m on his feeding schedule and not a pumping one? He isn’t keeping up with my milk supply and I’m trying not to pump (unless my boobs are rock hard and I’m uncomfortable) then I only pump till the discomfort is gone. I want to be able to keep breast feeding but I am worried I’ll lose my milk completely?
Hi Alexis! I am not an expert on nursing but your supply is determined by how much milk is removed – so if your son is removing all the milk he needs at the breast, I think you should be fine to pump less or not at all. I don’t think you will lose your supply completely. You might want to talk to an IBCLC about how to make the transition to nursing (since that is not my area of expertise) – you might want to gradually decrease the amount you pump rather than stopping all at once, and she might have strategies for overactive letdown if that’s a problem? I hope this helps! 🙂
I’m pretty sure this is what I have. My milk separates very fast and usually in a 5 oz bottle here’s about a 1/2” of “watery” milk on the bottom. How can add more fat to my milk? I pump about 2-3 times a day and get about 10 oz each session.
Hi Brandi! How long do you pump usually? The best way is usually to pump longer. Though if you’re pumping 2-3x per day they are probably already pretty long?