August 01, 2022 2 min read

I have had a lot of questions recently about the concern that one breast is producing more milk than the other, this is more noticeable when you are expressing, and you can directly measure and compare the ml's from your left and right breast. 



At least 70% of the time, your right breast could produce more milk than the left breast. This is not related to which hand you write with; or which breast you typically offer first to your baby when you nurse directly from your breast.


I have always joked that my breasts are sisters and not twins (just like my eyebrows 🤩) - they are not perfectly symmetrical, one may be slightly bigger. The same applies to your milk supply - it is unlikely that you will get the same milk expressed from each breast.


There are several contributing factors to this cause.

  • It can be that your mammary glands and milk ducts in one breast have a larger capacity than the other. **Please note, it will have nothing to do with the physical size of your breast as this is the breast tissue which affects breast size and not your mammary glands**
  • It could be your nipple size that differs and that the pump you are using is correctly fitting one nipple vs over the other nipple thus expressing more effectively from one breast. 


Here are a few ways you can encourage your 'slacker' breast to express more milk:

  • If you can breastfeed directly, offer your baby this slacker breast first. Generally, your baby will drink more from the first breast offered, and there is no one better than your baby to indicate to your body that you need to make more milk.
  • Use breast compressions and massage your breast while you are expressing.
  • Pump on this breast only between feeds. Set a schedule and try to express this breast more often to indicate to your body that you have a demand for more milk
  • Extra Power pump session on this breast only at least once a day over and above all feeds / expressing sessions. If you don't know how to power pump, download our free Tips & Tricks document HERE to show you a guide on power pumping
  • Ensure breasts are fully emptied after your baby has fed if you are directly breastfeeding. This can be done by expressing additionally after the baby has fed.


If you do have a slacker boob, you as a mother are by no means slacking and your body is working incredibly hard to nourish and feed your child. Even if your one breast does make less, generally your other breast will compensate for this and then produce more. Remember to keep well hydrated and ensure you are getting sufficient calories to breastfeed. An additional 330 to 400 kilocalories (kcal) per day is recommended for well-nourished breastfeeding mothers, compared with the amount they were consuming before pregnancy.


You have got this mamma, keep going!


If you are experiencing immense pain or having an issue with breastfeeding, please reach out to a lactation consultant who will be able to assist you. We recommend Niyati - click herefor her details.