How babies feed


We’re talking all about pumps and pumping in this guide, so why talk about how babies feed? 

Good question. We’re talking about babies, because pumps are designed to mimic babies. As best as possible. 

Pumps are a blunt instrument though. It’s rare that a machine is better than the real thing, but understanding the theory of what is happening might help you to use your pump in the best way possible to get the most out of your pump (and your breast).   

Here are the topics: 

👶How a baby sucks and swallows

👶How a baby stimulates your milk production

👶Why a baby may have trouble feeding at the breast

❔Common questions


How a baby sucks and swallows

A healthy baby uses her jaw to suck and compress to remove milk from the breast. But it’s not quite how you might first imagine it. 

Here’s a video explaining how your baby attaches at the breast. At about 1 ½ minutes in, there’s a graphic showing what’s happening on the inside of your baby’s mouth when she pulls back your breast. 

👆Video showing what is happening inside a baby’s mouth when she sucks (see 1:30 in)

Assuming the baby has a nice, deep latch (like in the first part of the video above) and is bringing the breast into her mouth, notice how she lowers her jaw? 

This creates suction (a.k.a vacuum or negative pressure for physics nerds out there) that helps to pull back the nipple, which draws milk out of the nipple into her mouth. You can see the milk collecting as a ‘bolus’ at the back of her mouth until she swallows it.  

She then compresses the breast with her jaw, and the ducts of the mammary gland within it, which stops (or slows) the milk coming out of the nipple and allows her to swallow the milk in her mouth and open her airway to breathe.

As an aside, Global Health Media has created lots of other videos, which have really clear explanations of breastfeeding, and they’re well worth a look if it’s something you’re interested in learning more about. 

So it’s not her closing her jaw that draws out your milk, it’s opening it. 

It seems counter-intuitive but think about a kitchen turkey baster. You put the long tube into the sauce, then you squeeze (compress) the bulb at the top. The liquid doesn’t actually run up the tube until you release the bulb. That’s because you’re creating suction by opening up the bulb.

By opening her jaw, your baby is ‘releasing the bulb’ and creating suction to draw out your nipple and milk. 

How do we know all of this? 

The science of milk ‘removal’ or ‘extraction’ has been studied for some time. Scientists and clinicians have looked at the biomechanics of sucking and breathing patterns of babies feeding at the breast and the bottle. 

Many studies have observed babies feeding, and other more recent studies used ultrasound to try to see what’s going on inside the breast and baby’s mouth. Until the ultrasound studies, there was some disagreement about how infants actually transfer milk from the breast, but that seems to have mostly been settled. 

So the big question when it comes to pump design is: how do we best mimic a baby’s sucking to draw out milk as effectively and comfortably as possible?

How a baby stimulates your milk production

It’s not just the mechanical sucking that your baby does to remove milk. There’s a lot more going on. 

Having skin-to-skin contact with your baby as they stimulate your nipple and massage your breast helps to stimulate milk production. 

Even if you’re exclusively pumping or supplementing with formula, you still benefit from having frequent skin to skin or nursing time (even if they’re not getting your milk) with your baby to encourage these hormones. 

Remember that when your baby massages or stimulates your nipple and breast and stretches your nipple in their mouth, they are helping to release your key hormones for milk making: prolactin and oxytocin.

Although the first few hours and days after birth are critical for priming receptor sites for your hormones to communicate with your milk-making cells, ANY time your baby is on your breast skin-to-skin  is beneficial. It doesn’t have to be only in those first few weeks of establishing supply. 

Why a baby may have difficulty feeding at the breast

Even when you and your baby are otherwise healthy, a baby can have difficulty feeding at the breast for all sorts of reasons. Rather than dive into issues with latch straight away, it can help to look at your whole feed session holistically. 

You might need to make little changes to how often you are feeding, when you start feeding (looking for hunger cues), how your baby is positioned, how your baby is latching, how their mouth is sealing to your breast, the rhythm of their sucking and jaw motion, your comfort, and even your nipple afterward. 

A good person to help you with this is a lactation consultant. If you’re unable to find an LC to visit in person, then try these hotlines and other supports

Common questions on how babies feed

Have we not answered your question yet? 

Here are some common questions we hear on this topic.

How can I stimulate milk production?

One of the simplest ways to stimulate your milk production is to have skin-to-skin contact with your baby. Prolactin and Oxytocin are your milk-making hormonal allies and these are triggered when your baby stimulates your nipple, stretches is back, and massages your breast. 

Why do babies feed more at night? 

In the early weeks, when your body is establishing your milk supply (remember supply and demand), it is normal for your baby to want to feed every 2-3 hours. New babies will typically wake several times in the night to feed. Your baby may wake because they are hungry, but they may be waking for other reasons - like being hot or cold, or uncomfortable. Although it’s difficult not to compare “sleep notes” with your friends and wonder why your baby is feeding so much at night, remember night waking is the biological norm for babies. 

When should I first feed my baby?

Ideally it is best to start trying to breastfeed your baby in the first hour after birth. By latching and rhythmically sucking, your baby helps to kick-start your hormones into producing milk. Your baby might not feed at first. But even if they don’t, it’s good to get them on your chest skin to skin, as soon as they’re born to give them all those benefits of skin to skin, as well as access to your breast and the opportunity to start learning to feed. 

For more on the science behind skin to skin, read this Cochrane review, which found that skin to skin contact should be normal practice for healthy newborns born from 35 weeks, even if you had a c-section. Scroll down a bit to get to the “plain-language section” for the most readable part. As usual, they also find that there’s more research needed.

How often should I feed my baby?

Usually a newborn baby will nurse about 8 to 12 times in a 24-hour day. This works out to be about every one to three hours. As you establish your milk supply and your baby becomes more efficient at feeding, these nursing times will begin to get less frequent.

Why won’t my baby feed at the breast?

There are a whole variety of reasons why your baby might be having difficulties feeding. It could be your baby’s latch, hunger cues or positioning, even your comfort levels - it’s really difficult to know exactly why, especially if you’re tired and struggling. 

If you’re having issues, the best person to help you is a qualified lactation consultant. If you’re unable to find an LC to visit in person, then try these hotlines and other supports

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