You have been pumping your breast for a few months, and have noticed that one breast seems to produce more ounces than the other. A research from Academy of breastfeeding says differences in the milk output from the right and left breasts are common, and that milk output is often greater from the right breast. "What does cause my milk supply uneven and how do I balance it?". 

Here are some of the reasons why one breast may produce less milk than the other and things you can do to even out your milk supply.

Why One Breast May Produce More Milk?

• Less Mammary Tissue

Your mammary tissue (sometimes referred to as “glandular tissue”) is the tissue in your breast that produces breast milk. When you become pregnant, this tissue increases. It is part of why your breasts are sore at the beginning of pregnancy! The tissue increases even more when your baby is born and your milk “comes in.”

it is normal for breast anatomy to have variation and for one of your breasts to simply have more mammary tissue than another. This can be a reason why one of your breasts produces more milk than another, and why your baby may prefer one side over another.

• Trauma To The Breast

Trauma to the breast—from incorrect latching, using a pumping flange that is too tight, or experiencing an injury to the breast or nipple—could cause one breast to produce more milk than another. However, this is a less common cause of uneven milk supply.

• Previous Surgery

Having a previous breast surgery might affect milk supply in one of your breasts. Surgeries that have the potential to affect your milk supply include any surgery that might have cut the milk ducts or nerves in your breasts, such as breast augmentation surgery or breast reduction surgery.

How to Balance Out Your Milk Supply

If you are finding that your uneven milk supply is causing issues such as a decrease in overall milk supply, frequent engorgement or breast infections, there are some things you can do to even out your milk supply.

• 2 motor pumping

While it may be obvious that double pumping saves time, It is one of the best way to balance your milk supply. With use of 2 motor breastpump, adjust the pumping level for each side of breast. Medela research team knew there were also studies that suggested this method helped mother express more milk.

It prompts an extra let down. Of course, babies are the experts when it comes to getting mother’s milk. But double pumping gets closer to what they can do. One theory is that even though a baby drinks from just one breast at a time, he normally has lots of close contact with his mother while doing it, which is great for releasing oxytocin. Perhaps because double pumping involves double the contact and stimulation, it works in a similar way, prompting additional oxytocin release and consequently more milk.