One Breast Or Two Per Feed?

Should a baby have one breast per feed or both sides? This article looks at how breastfeeding works to help understand whether a baby needs one breast or two per feed, how often a baby might want to breastfeed and what to do if a baby needs more milk.

Breasts make different amounts of milk

How much breast milk a breast can store varies from mother to mother and even from breast to breast within the same mother. How much breast milk a breast can store is known as the storage capacity. A mother with a small storage capacity can make just as much milk in 24 hours as one with a large storage capacity but she will need to feed her baby much more often.

Size doesn’t matter

It’s not possible to tell how much breast milk a mother’s breasts can store by looking at purely the size of the breasts because the amount of fatty tissue will control the cup size. It is the amount of glandular tissue (milk making tissue) within the breast that controls the amount of milk stored between feeds. So how can a mother know what her storage capacity is and whether her baby needs one breast or two per feed?

One breast or two per feed?

Let your baby decide! The only person who can tell you how often he needs to feed is your baby. Only your baby knows when one breast is empty and whether he needs the milk from another breast straight away to fill him up or in half an hour or two hours. Put another way, if a mother can store 50ml in each breast her baby might want both breasts per feed. Whereas the baby of a mother who stores 120ml in each breast may only want one breast per feed. You don’t need to know how much milk is stored so long as a baby is:

  • fed on demand
  • allowed to finish the first breast of his own accord before offering the second side (or third or fourth)
  • has plenty of dirty nappies and is gaining weight appropriately and thriving

All breast milk is good

You may come across the idea that there are two kinds of milk in a breast; low fat foremilk at the start of a feed and high fat hindmilk that arrives towards the end of a feed. Taken a step further you may have heard that the foremilk is like a drink or a soup starter but the hindmilk is the more important “meal” and “pudding”. It can be confusing and unhelpful to think of breast milk in terms of two kinds of milk because all breast milk is good. See Forget About Foremilk and Hindmilk to explain why you don’t need to worry about this. Confusion about foremilk and hindmilk can lead to harmful advice such as in the following example.

My health visitor told me to keep to one breast per feed to reach the hindmilk

Keeping to one breast “to reach the hindmilk” is a very common myth but is poor general advice because:

Staying on one breast can reduce a milk supply

Keeping a baby on one breast per feed—or for a specified block of time—is generally a way to decrease a breast milk supply. Offering the other breast after your baby has finished the first side, or switching between breasts (see box) is generally a way to increase a milk supply.

  • If you have a low storage capacity then keeping to one breast is potentially denying your baby half his milk or more. Your baby may need the “hindmilk” from both breasts.
  • If you have a high storage capacity and an abundance of milk, keeping to one breast per feed, or for a block of time, may work well.

If you are not sure whether you have a low or high storage capacity, check with an IBCLC lactation consultant who will take a full history and check on your baby’s weight gain and dirty nappies.

Switch nursing involves switching (changing) breasts a couple of times during a breastfeed to keep a sleepy baby feeding and can help to increase milk supply. Start by letting your baby feed on the first breast until their sucking slows right down or stops and then move him across to the other breast. The faster flow of another let down on the second side will keep him interested in feeding, then, once sucking slows on this breast, swap back to the first breast and so on. Switch nursing can be combined with breast compression; once sucking slows on each side try breast compression to keep your baby feeding actively before offering the next breast.

An underweight baby needs more milk

When weight gain is an issue, the answer is almost always that the baby needs more breast milk rather than a few more drops of higher fat milk from one breast:

When a baby isn’t gaining weight they most likely need more milk, not more time on an already empty breast which will further reduce a mother’s supply. An extra 7-8 ml of high fat milk from the same breast is no substitute for the extra 70-80 ml of fore-hind-and-in-the-middle-milk they might need from the other breast.

Making more milk

Breasts make milk on demand; so that the faster your baby drinks the available milk, the faster your breasts will make more milk to replace it, indefinitely. Breasts gauge demand by their degree of fullness:

  • Whenever a breast is full, milk production slows down
  • Whenever a breast is emptied regularly, milk production increases

More frequent feeds, breast compressions, and using both breasts per feed are all strategies to make more milk and see How to Make More Milk on this website.

Breast milk is easily and quickly digested—even as quickly as one hour

Sometimes one breast, sometimes two

Let your baby decide whether he wants one breast or two per feed and whether he wants to feed again in 30 minutes or two hours. Start each new feed with the breast that baby finished on last. Breastfeeding authors Mohrbacher and Kendall-Tackett explain:

Once your milk increases on the third or fourth day, most babies take one breast at some feedings and both breasts at others. This strategy relies on your baby’s ability to tell you what he needs. As with us adults, some babies are fast eaters and some are slow eaters. So a clock will never tell you when your baby is done. (How would you feel if, in the middle of your meal, someone pulled your plate away?) Only your baby knows for sure when the flow on one breast has slowed down to the point where he is ready for the other side. Only he knows when he has had the right amount of milk for that feeding.


It’s very common for one breast to have more milk than another or for a baby to have a favourite side—perhaps they prefer one nipple over another or the flow of milk on one side feels just right. Over time the favourite side will usually compensate and produce more milk while the least favourite side will slow down production. This can cause breasts to be lopsided for a while but after breastfeeding ends they will even out again. If a mother is concerned about the size difference

  • Try to recreate the same position from the favourite side on the other breast. For example if baby prefers the cross cradle hold on the left side, try rugby hold on the right so that baby’s body position on that side mimics their position on the favoured side.
  • Pumping with a good breast pump can help to increase the milk supply on the least favourite side—when there is more milk it is likely to be more desirable again to your baby.

What if my baby falls asleep at the breast? Is this a bad habit?

It is quite normal for a baby to enjoy sleeping in his mother’s arms with the breast in his mouth, sometimes this is called comfort nursing. Breastfeeding your baby to sleep need not be a problem when coupled with good weight gain. However, watch for the baby who “hangs out at the bar without buying any drinks” i.e. he is latched on but actually he is barely swallowing anything before getting tired and falling asleep half way through the first side. Consult with your IBCLC if this is the case to get breastfeeding back on track with a care plan tailored for you and your baby and check out Breastfeeding a Sleepy BabyIs My Baby Getting Enough Milk? or Baby Not Gaining Weight. For more information about comfort nursing see Flutter Sucking and Comfort Nursing.

I’m still not sure when to feed him!

When your baby shows early feeding cues such as sucking his fist or fingers, or moving his head side to side with an open mouth; offer him the breast. If you miss the early cues he may have to cry to get your attention, but you don’t have to wait for crying; babies latch best when they are calm and before they get ravenous.

Breast milk is easily and quickly digested—even as quickly as one hour—and babies have tiny tummies so they need to feed little and often. It is usually recommended that a baby has at least 8-12 feeds in 24 hours i.e. that they breastfeed every two to three hours from the start of one feed to the start of the next and this ties in with a newborn’s sleep patterns. Some babies may feed more frequently e.g. every hour at first. Frequent breastfeeds will provide plenty of breastfeeding practice, provide baby with a steady supply of food and stimulate the breasts to make more milk.

How can I tell my baby has finished feeding?

Check that your baby is feeding well by watching his jaw move and listening for swallows, there is more information in Is My Baby Getting Enough Milk? As the feed progresses his rhythmic sucking will slow down to flutter sucks with less frequent swallows; he may fall asleep and/or let go of the breast to signal he is finished. If you feel he hasn’t drained the breast properly or has fallen asleep before he finished, you can try some breast compressions to get him sucking again, when he stops sucking with the compressions, offer the second side. Sometimes he may want the second side and sometimes he might not.

Offer the breast frequently

There is a lovely passage in the Womanly Art of Breastfeeding that helps explain how often to feed a baby by comparing the breast to a snack tray:

When you’re at a party, the hostess doesn’t usually ask if you’re hungry before she passes the snack tray. She offers frequently, and you decide whether to eat or pass it on. You’re the one with the breast “snack tray”, why not be a good hostess and offer whenever your baby seems unsettled? No need to force the issue if you’ve guessed wrong. But your baby can’t nurse if the offer isn’t made.

Isn’t he just using me as a pacifier?

Not at all! Nursing feeds him, pacifies him, puts him to sleep, comforts, reassures and relaxes him. If you offer your breast only as food and not as a “pacifier”, you’ll cut out all the calories he gets along with those other reasons, you’re more likely to end up with supply problems, and you’ll lose the pleasure of—literally—going with the flow. The phrase “he’s just using you as a pacifier” works against confident, smooth-running breastfeeding. Nursing is how a baby grows; why hold back?


Breasts vary in their breast milk storage capacities. Where one mother’s baby might only want one breast per feed and not be hungry for two hours, another may need both breasts per feed and be hungry again in an hour. Let your baby decide how many breasts he wants at a particular feed by looking for his feeding cues and offering him plenty of opportunities to breastfeed.