How to Fix Lopsided Breasts When Breastfeeding (aka Slacker Boob)

Do you find yourself getting less milk from one of your breasts when you pump? It’s normal – though a little annoying – for one breast to be a “slacker boob” or “lazy boob” and underproduce compared the the other side. Here is why that happens, and how to fix lopsided breasts when breastfeeding.

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What causes uneven milk supply when you’re breastfeeding?

There are a few things that can cause you to get (for example) 4 oz on one side and only 1-2 oz on the other. In many cases, there is a normal physical difference between the two breasts; for example, one side may have more working milk ducts than the other.

Also, if your baby nurses or has nursed in the past with a preference for one side over than the other, that also could have caused that side’s supply to increase over time compared to the other one.

Finally, it could be a result of your own preferences for doing breast compressions or single pumping one side earlier on. (I’m definitely guilty of doing more compressions on my left side, which is my higher-producing breast.)

How common is it to have a slacker boob?

Very, very common.

I did an unscientific poll on instagram, and of the 1,969 people who responded, 94% consistently experience uneven milk supply when pumping.

Four ways to fix your slacker boob and increase milk supply in one breast

You might want to increase milk supply on the slacker side because you want to pump more milk in general (and why not start with the side that’s lazy?) or because you don’t like the appearance of lopsidedness.

In order to even things out, you will want to try to pump the same amount of milk from your good side, and more milk from the slacker side.

The more milk your baby – or in this case, your breast pump – demands, the more milk your body will supply. Therefore, you want to demand more milk from the lazy side, which means pumping more. Additional pumping can trigger more letdowns, which means more milk being removed from that breast, which then will result in your body making more milk in that breast.

Therefore, your goal in continuing to pump more milk from the lazy side is to convince it that it needs to make even more milk. (When you do this, make sure you don’t change anything with how much you’re pumping on the good side! You don’t want to jeopardize your supply on that side or end up with a clogged duct or mastitis.)

Here are a few ways you can do that. Note that it will take some time – probably about a week – to see an increase in milk output on the slacker side, because it takes a few days for your body to ramp up milk supply in response to increased demand.

1. At the end of a pumping session, keep pumping the slacker side for a few extra minutes.

To do this, after you finish pumping for your normal amount of time, you’d stop the pump and set yourself up to single pump only the slacker side.

(Most double electric breast pumps allow you to single pump by detaching the tubing from your pump parts on one side and covering that side’s tubing port. Check your pump’s instruction manual if you’re not sure how to do this – most manufacturers have them online.)

On your good side, you can either leave your pump parts and bottle in place without the tubing connected or put a breast pad on that side, because when your milk lets down again, it will let down from both sides. This way, you won’t leak milk all over the place.

Start the pump in the letdown/massage phase and shift into the expression phase after a few minutes. You can stop either after the next letdown is finished, or after 5-10 minutes is up. (Even if you don’t get another letdown, the additional nipple stimulation may help.)

2. Do most of your breast compressions on the side that doesn’t produce as much milk.

Breast compressions can be a great way to get more milk when you pump. If you don’t want to pump any more than you already do, you can focus your efforts on getting more out of the lazy side while you’re already pumping.

To do breast compressions, massage the low performing side while you pump, moving your hands around and pushing as much milk out of the milk ducts as possible. Take a break every few minutes to let your hands rest and then start again. Note: It’s much easier to do this with a hands-free bra.

3. Add an extra pumping session for only the lazy side.

If adding a few minutes to each session doesn’t work for your schedule, you can try just adding one pumping session for day that is just for the low-producing side.

To do this, hook yourself up on just the lazy side, and pump for 10-15 minutes. Use a milk catcher or breast pad on the other side to prevent leaks, because as mentioned above, your milk will let down on both sides.

At the next pumping session, you’d pump as you normally would on both sides.

4. Power pump the low-producing side.

Power pumping is an attempt to simulate cluster feeding. To do it, you pump on and off for about an hour – generally 20 minutes on, 10 minutes off, 10 minutes on, 10 minutes off, and so on, though the exact intervals don’t matter much.

More details about power pumping are available here, though obviously keep in mind that you’d just be doing it on one side instead of two.

Do I need to fix my lopsided breast situation?

No, having one breast that produces less milk than the other won’t hurt anything. If the difference in output or the appearance of the unevenness bothers you, then you should try to fix it. However, if not, having uneven breasts is totally normal and having a lazy boob won’t hurt anything.

Regarding the appearance of unevenness, it’s likely that other people won’t notice it. But if it makes you self-conscious, using a couple of extra breast pads in the low-producing side might help.

Have you successfully fixed a slacker boob? Let us know how you did it in the comments!