Let me start by saying I’m an EBF (exclusively breastfeeding)  mom of a beautiful one year old girl. Now, she’s been interested in solid foods since she could grab them but she still nurses every four hours or so. I’ve never been able to pump very well so I gave it up after two months. My breasts wouldn’t react to a machine the way they do when my baby nurses, and I would only get half an ounce from each breast, which is completely normal for some moms. If you want to read about how to improve pumping, I suggest checking out http://www.workandpump.com.
Once we got our routine down and we were both comfortable, my daughter began to prefer the left breast over the right. Soon, she simply refused to nurse from the right breast. After a while it became known as “the other boob.” The unwanted, sad, smaller, still slightly engorged boob. After lots of struggling I figured out that she would nurse on that side at night when she was sleepy. Even though she started to nurse again after a three month strike, things never really went back to normal. My milk supply dwindled on that side, she still refuses the other boob during the day, and she’ll only nurse for a few minutes at night, I assume because there’s not a whole lot of milk there compared to the favorite. 
All breastfeeding moms know there’s quirks when it comes to being your babies dinner. Once you get the right position down for a few weeks baby changes their mind and you have to start all over. Once you finally get in a solid routine your little one might decide one boob is better then the other. Why? There’s a variety of reasons. 
Your letdown could be stronger on one side or the other. Most babies- especially older infants- seem to prefer a faster flow of milk when they’re eating. Once your baby chooses a side, milk production in the other boob will go down if you do not pump regularly,  so even if they start nursing on that side again they may only nurse for a few minutes before wanting to switch to their regular side for more food. Try switching back to the “other boob” once they’ve finished on their preferred side. 
Your nipples aren’t the same shape or size- no matter how long you stare at them. Maybe one nipple is easier to match on to. Shape and size are a big factor in baby nursing. A lot of babies have a preference for a certain nipple on a bottle, same goes for your own nipples. If your breast is engorged your little one might refuse that side as well, so try to express some milk before hand and see if that helps.
Some babies just like laying on one side versus the other. Perhaps try a different position with the other boob so baby isn’t laying on its side. Perhaps the football hold or try laying on the bed with baby and nursing side by side. Because your liver is on the right side of your abdomen, lying on your left side helps align your esophagus to your stomach, so a baby may favor laying on their left side because it’s easier to swallow and keep their food down without giving them an upset tummy. 
When babies don’t feel good they will sometimes nurse for comfort. When it comes to something like an ear infection or getting shots they’ll be sore and may choose one side over the other. Make sure you check with baby’s doctor if something seems off or if baby seems like they’re in pain. Babies will often refuse to nurse while they’re teething because sucking can cause discomfort for their already sore and swollen gums. 
Can I even the girls out?
You can try pumping as much as possible on the neglected breast. After baby is done eating try pumping your “other boob.” This will help keep your milk supply up and decrease shrinkage. Other then that I have not found a cure for the lopsided ladies. If they’re sore from engorgement or your breasts don’t react to a pump like mine, try soaking in a hot bath and pumping. The warmth can sometimes get things going a little faster and ease pain. I do not recommend drinking fenugreek tea or using other OTC methods of upping your milk supply, however I will say DRINK WATER! Get into the habit of drinking a glass of water every time baby nurses. This will help.
Either way, once baby chooses a side we’re left with a decreased milk supply in the other boob. The sad boob. The smaller, less fortunate boob. And as much as you try to pump or get baby to latch, other boob just won’t be the same as the favorite. And that’s okay. Why? Because baby is still happy, heathy and getting fed. You’re still getting all the wonderful bonding time with your little one that will pass too soon. And you’re still as strong as ever for sticking with breastfeeding through all of its ups and downs. Way to go mama! Other boob will have its day again, but for now, let that beautiful baby of yours nurse that liquid gold your amazing body creates. Bask in the awesomeness that our bodies create. 

Jessy Starlin

I'm a single stay at home mommy of a beautiful one year old girl. I'm an exclusively breastfeeding, co-sleeping mommy, although my little girl is growing up and now eats solids. Ever since high school I've loved writing. Now that I'm older I can put it to use through my articles.