Turns Out, You Can Have Oversupply In Just One Breast

by Cat Bowen

I don't know about you, but my breasts are not 100 percent symmetrical — my left breast is a bit bigger. When I was breastfeeding, this size difference was magnified by my milk. I wondered if it was oversupply. If so, why do I have oversupply in just one breast? If my child is breastfeeding from both equally, why the difference?

Hypergalactica sounds like the next Marvel movie, or perhaps the name of Wonder Woman's long lost aunt, but it's actually the technical term for the overproduction of milk in the breast. When it only happens on one side it's called "bilateral hypergalactica." It is not as uncommon as you may think, according to Breastfeeding USA, and usually self-corrects. However, it can be quite painful for you and not easy on your baby, either. According to La Leche League International, it can cause your baby to gag, your breasts to be quite tender and hard, and it even affects baby's weight gain and the quality of their stool. While it's less common to experience the phenomenon bilaterally (one breast) than unilaterally (both breasts), it does happen. The reasons for its bilateral presentation are as varied as the reasons for the diagnosis of hypergalactica, according to the Journal of American Board and Family Medicine.

Kelly Mom suggested that oversupply in just one breast could be as simple as basic anatomy. Your body isn't symmetrical, and it tends not to function symmetrically. But it may also be due to breast preference by the mother or the child — maybe you tend to start your baby on the left breast because you're right-handed, and you just fall into a pattern. But there could also be other causes, Colleen Williams, International Board Certified Lactation Consultant (IBCLC) tells Romper.

"First things first, you need to address whether or not your breast has mastitis. If you've only recently started producing far more in one side than the other, it might be because of mastitis, and that needs treated," Williams says. Are one of your breasts more tender or warm to the touch? Rocky feeling? Williams notes these as things you need to consider when examining your breasts because mastitis can cause both oversupply and undersupply.

"You also need to determine if your baby is favoring one side because they have an ear infection. Babies often want to lie on the infected side and will tug at their ears, or make a 'click' sound when they nurse because it may hurt to swallow. Also, they might have a birth injury that has gone unnoticed thus far, and makes one side more comfortable than the other, but that is far rarer in my experience than an ear infection." She suggests that a good way to see if your oversupply in one breast is caused by baby's preference is to feed them in the "uphill" position, which is belly to belly, with baby's feet pointed at your own, so that they're not on their side at all, but on their tummy.

Williams tells Romper that after everything's been examined, you may find that your baby, or you, simply prefers a side, and you fall into habits that just need adjusting. But it's entirely possible to correct those habits and most times, oversupply is treatable.

If you are experiencing bilateral hypergalactica, or as I referred to it "loppy boobs," it's best to be seen by a healthcare provider so your doctor and lactation consultant can address you, your baby, and your lopsidedness. Until then, you can always stack nursing pads on one side to even out your bra. It worked for me, plus it will help control that one leaking geyser of a breast you have thanks to oversupply.