Foremilk/Hindmilk Imbalance: How to Fix It

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 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 you have one, and how to fix it.

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.

An imbalance can result in your baby becoming gassy, fussy, having colic symptoms, and having green poop.

What are the causes of foremilk/hindmilk imbalance?

In babies that nurse, this can happen if the baby is frequently switching breasts during a nursing session and gets foremilk from each side, but then they’re full so they don’t continue eating – therefore, they don’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, many exclusive pumpers have written to me and said that they don’t feel like their milk has “enough” fat in it and they don’t see their milk separate much in the refrigerator.

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.)

What should you do if you’re exclusively pumping and think you have a foremilk/hindmilk imbalance?

There are a few things that you can try.

• Pump for longer. If you are concerned that there isn’t much fat in your breastmilk, the 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 doing breast compressions to empty your breasts faster.
• Dump the first ounce. If you have an extreme oversupply (say, you’re pumping over 50-60 ounces per day), and you think you have too much foremilk, you can always 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. If you want, you can freeze this milk and save it to mix with cereal, oatmeal, or purees when your baby is old enough for solids.
• Keep milk from pumping sessions together. Some moms pour everything they pump in a day into a pitcher, and then divide it out into bottles at the end of the day. That’s totally fine to do; however, if you’re having issues with too much foremilk, you can 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.

Have you dealt with foremilk/hindmilk imbalance? Or been worried about green poop? Tell us about it!