What to do if your baby only nurses on one side

Why is my baby refusing one breast?

Infants, especially newborns, may have periods of preferring one breast to the other. You may notice your baby fussing, pulling away, or simply refusing to nurse from one of your breasts.

A newborn may reject one breast because it's harder to latch on to for some reason. The rejected breast may be more engorged or have a difference in the nipple, for example.

An older baby may reject one breast because it has a low milk supply or a slower flow or letdown than the other breast. Your baby's breast preference can make the milk supply situation worse: You can end up with a low milk supply in one breast if your baby nurses more often from the other one.

Sometimes a baby will be more comfortable being held on one side than the other. If your baby seems to suddenly prefer one side, it may be because something hurts them. Maybe they have an ear infection in one ear, or maybe the side that they were just immunized on is tender, for example.

If your newborn is refusing to nurse on one side, ask their doctor to check for birth injuries. Some babies will have an injury that goes unnoticed at birth, but causes them discomfort in certain nursing positions.

If you've had surgery (or have another physical difference) in one breast, you may have a lower flow of milk in that breast. It's not common, but having cancer in a breast can also result in low milk flow. If you think that one of your breasts isn't producing as much milk as the other, talk with your healthcare provider.

What can I do if my baby only nurses on one side?

Try to gently and persistently encourage your baby to nurse at the less-preferred breast by always offering that breast first, when they're hungriest. Or, it may work better to offer that breast when your baby is partly full and sleepy.

You can also try offering the less-preferred breast when your baby is just waking up and perhaps still sleepy enough to take it. Experiment with different positions, and perhaps rock or sway your baby while nursing.

Another strategy is to start your baby on the preferred breast and then slide them over to the other breast without changing the position of their body.

If your baby seems to want a faster flow from the less-preferred side, try doing breast compressionsOpens a new window to speed the flow of breast milk.

If the less-preferred breast is engorged and your baby is having trouble latching on, try hand expressing or pumping just enough milk to soften the breast and make your areola compressible.

How can I avoid engorgement on one side?

If you're consistently nursing from one breast, you'll want to pump or hand express milk from the other side to avoid engorgement and keep up production. You may need to use the expressed milk to supplement your baby's feedings – though you may find one breast produces all the milk your baby needs.

Engorgement happens when a breast becomes overfilled with milk. You'll know you're getting engorged if your breast feels uncomfortably full, swollen, warm, throbbing, or painful. Your nipples may become flattened. If the swelling is severe, your breast may be so full that the skin looks shiny.

Do I need to switch breasts while breastfeeding?

If your baby is getting enough milk and their breast preference poses no real adversity for you, there's no harm in letting your baby nurse from one side only. (For example, you may want to keep nursing on one side while you pump on the other.) There are plenty of women who have nursed successfully from one breast only.

If you end up nursing on one side only, that breast may be larger than the other. But once your baby is weaned, your breasts will go back to more or less the same pre-nursing size.