Breastfeeding and supplementing premature babies

How do I breastfeed and supplement my premature baby?

Premature babies benefit greatly from breast milk, but breastfeeding may be hard for them because they are not fully developed. The key is for mothers to establish and maintain a milk supply by expressing. Mothers generally need to continue expressing until their babies breastfeed well enough to get all the milk they need from the breast and are a little past their due date. Ideally, the first feeding is at the breast, but premature babies who cannot breastfeed may need to receive their first nutrition by needle into a vein (parenteral nutrition) or their first milk by tube into the stomach (feeding tube). Other feeding tools such as nipple shields, cups, and bottles can be used as the baby learns to breastfeed. Over time, these babies become stronger and start taking more milk from the breast. 

A) Breastfeeding challenges when babies are premature

1) The impact of prematurity on breastfeeding 

Premature babies are less likely to be breastfed and tend to breastfeed for shorter periods than full-term babies (Colbourne 2020; Fan 2018). One study (Parker 2019) showed that in 2017, only half of very small babies in the U.S. were receiving breast milk when they left hospital, with the others receiving infant formula.

Sucking begins from 18 to 24 weeks after conception. However, babies born earlier than 34 weeks often have trouble organizing their sucking, swallowing, and breathing, resulting in low oxygen levels, the temporary stopping of breathing (apnea), and milk getting into the lungs (Lau 2016).

Even after 34 weeks, babies struggle to breastfeed as (Geddes 2017; Jonsdottir 2020; Lapillonne 2019):

  • They have smaller mouths.
  • They have less mouth and suction strength.
  • They tire out quickly.
  • Their brain and nervous system are still developing.
  • They may not wake up to feed.
  • They are often asleep after breastfeeding, even if they did not take in enough milk at the breast.

Until the baby is stronger, mothers and health-care providers need to closely watch the baby’s growth and ensure it is normal.

2) Other challenges to breastfeeding

Babies have even lower breastfeeding success when they (Parker 2021):

Health challenges of the mother of baby may further affect their ability to breastfeed (Parker 2021).

B) Learning to breastfeed

As babies develop and learn to breastfeed, they move through a series of steps, including:

  1. Waking up.
  2. Latching.
  3. Sucking.
  4. Developing normal sucking patterns.
  5. Getting some milk from the breast.
  6. Breastfeeding effectively and no longer needing milk supplements.

The above steps are easier for some babies than for others. In general, the more premature the baby, the more support the baby needs, but even babies who are born just short of full term can have significant breastfeeding problems.

C) Time at the breast

Very small premature babies usually receive most of their milk by feeding tube.

1) Nuzzling

They often start their breastfeeding experience just by being in contact with the breast. They start by licking and mouthing the nipple and then start to hold the nipple in the mouth without sucking. These behaviours are called nuzzling.

2) Non-nutritive sucking

Babies who are medically stable and interested in breastfeeding but unable to take milk by mouth are allowed to suck on a breast that has just been expressed.This is called non-nutritive sucking and it:

  • Helps the baby practice sucking and get started on breastfeeding.
  • Provides stimulation for the baby’s gut.
  • Improves the digestion of milk.
  • Allows the baby to get the good bacteria on the areola.
  • Helps to increase a mother’s milk supply.
  • Calms the baby.
  • Helps to relieve the baby’s pain.

Non-nutritive sucking can also occur if the baby is not breastfeeding effectively

D) Sucking at the breast

Mothers are encouraged to offer the breast as soon as possible (Parker 2021). Ideally a baby’s first feeding by mouth is at the breast. Premature babies whose first feed is directly from the breast instead of a bottle have higher breastfeeding rates when they leave hospital (Casey 2018). Babies who have medical complications and are switched to the breast once they are stable, learn to feed more quickly than those who were given bottles or cups (Medeiros 2018).

Breastfeeding may even shift the types of bacteria in the mother’s milk (microbiome) to favour ones beneficial for the baby (Biagi 2019).

Premature babies at 34 to 37 weeks after conception still have many breastfeeding challenges (Pike 2017). It is very normal for babies to have different breastfeeding sessions over the course of one day. Babies may:

  • Not wake to feed.
  • Wake but not be able to latch onto the breast.
  • Latch but not suck.
  • Latch and suck but only take in very small amounts of milk.
  • Latch and suck and take in enough milk.

Sometimes they look as if they are feeding well, with good sucking for 10 to 20 minutes, but they only take in very small amounts of milk. We call this the Big Show! It can be identified by using before-feed and after-feed weights.

If you are using breast compression while expressing and find it helpful, you can use the same technique while the baby breastfeeds to increase the amount of milk the baby takes in. You need to ensure that it does not interfere with the latch and the feeding. Mothers with smaller breasts are generally less able to combine breastfeeding and breast compression without disturbing the baby.

If the mother’s nipple is too big for the premature baby’s mouth, the baby may take longer to develop the ability to latch onto the breast.

All of these behaviours and challenges are normal and part of the progression to full breastfeeding.

E) Getting milk from the breast

Over time, premature babies become stronger and consistently start taking more milk from the breast. The rate at which this happens is different for each baby with some exclusively breastfeeding as early as 40 weeks after conception and some never learning to breastfeed. Babies who are able to breastfeed tend to continue breastfeeding for longer periods than those who are only fed expressed breast milk (Pinchevski-Kadir 2017).

Babies who are fed when they show hunger signs, instead of on a schedule, tend to grow better, breastfeed well sooner, and leave hospital sooner (Fry 2018).

Breastfeeding babies must be monitored closely to make sure they are taking in enough milk.

F) Supporting the premature baby at the breast

1) Limit the baby’s stress

Whenever the baby is brought to the breast, remember to minimize the baby’s stress. This allows the baby to focus on feeding and not become sleepy or unstable.

Mothers can use the cross-cradle, under-arm, or laid-back hold to position the baby at the breast. The laid-back hold in particular supports the premature baby’s abilities and appears to decrease stress.

When offering the breast, be patient and stop as soon as the baby is stressed, unable to feed, no longer interested, or asleep.

2) Nipple shields

Premature babies often benefit from using a nipple shield as they develop the ability to breastfeed (Clum 1996; Meier 2000). A nipple shield works in a number of ways to help babies latch, suck, and get more milk from the breast. 

There are different styles and sizes of shields. In general, smaller babies need smaller shields. Using a shield is relatively simple, but some mothers have large nipples and may not be able to use a smaller shield. Nipple pain caused by a shield should be addressed.

A nipple shield should only be used if it helps the baby. Not all babies benefit from a nipple shield. They use the shield until they are able to latch and transfer milk just as well without a shield as with one. This usually happens around 42 to 46 weeks after conception. Some babies make the transition to the breast earlier but it may take longer for others. There are a small number of babies who will need a shield for the whole time that they are breastfeeding.

G) Supplementing tools

Until premature babies can breastfeed effectively, health-care providers rely on various tools to feed premature babies. The type and amount of supplement and how it is given depends on the following:

  • Health and abilities of the baby.
  • Age of the baby.
  • Families' preferences.
  • Caregivers’ preferences.
  • Hospital policies, practices, and resources.

1) Total parenteral nutrition

Extremely premature or sick babies who cannot tolerate or digest milk are fed by needle into a vein using a special liquid in a process called total parenteral nutrition, or TPN. This continues until the baby can start digesting milk.

2) Feeding tubes

Babies who cannot breastfeed effectively or safely but can digest milk are fed using a feeding tube placed through the baby’s mouth or nose and into the stomach. Once in place, a feeding tube is a gentle and effective way to feed a baby. It allows the baby to get milk without making any effort. The baby may even sleep during feeds.

When using a feeding tube, health-care providers can measure exactly how much milk a baby takes in. The tube allows babies to practise and learn breastfeeding while ensuring they receive all the milk and nutrition they need. Babies can breastfeed before or during the time they receive milk through the tube.

Feeding tubes are removed when:

  • The baby can breastfeed effectively.
  • The baby does not tolerate the tube.
  • The baby is getting ready to go home.

3) Cups and bottles

In some hospitals, the feeding tube is removed while the baby still needs supplements to breastfeeding. Supplements are then given by another means. Options include bottlescups, finger-feeding, or a tube-at-the-breast system.

Bottles are sometimes viewed as easier or less work than breastfeeding for premature babies but this is not supported by evidence nor does bottle use result in babies leaving hospitals earlier (Chen 2000; Berger 2009; Wener 2021).

H) The baby’s milk options

The amount of milk a premature baby needs is based on the baby’s weight. A common amount is 150 millilitres/kilogram/day (2.3 U.S. fl oz/lb/day). This may be adjusted by health-care providers depending on how fast they are growing and their health and ability to tolerate milk feeding.

There are a number of milk choices for premature babies. As with term babies, the mother’s own colostrum and breast milk are always preferred because of its many benefits. The other milk choices in order of preference are donor human milk and infant formula.

1) The mother’s own colostrum and breast milk

Premature babies who are unable to breastfeed should be given their mother’s colostrum as soon as possible after birth. This helps to:

  • Protect the baby from infection (Lee 2015).
  • Shorten the time in hospital (Romano-Keeler 2017).
  • Increase the rate of breastfeeding success after discharge (Snyder 2017).

The key to having breast milk is for mothers to establish their milk supply as this will determine the eventual amount of milk produced. They must also maintain their milk supply after their milk comes in. There are numerous reasons for mothers of premature babies to be at an increased risk of a low milk supply.

Mothers who know they will be delivering prematurely may consider manually expressing colostrum (prenatal expression) before the baby’s birth. This may limit the need for infant formula. Please discuss this with your health-care providers as it may stimulate early labour.

In general, expressed colostrum and milk should be used in the following order:

This order may be especially important for vulnerable premature babies. Freezing will kill infection-fighting white blood cells and helpful bacteria. Mothers who express more colostrum and milk then the baby needs should give the baby fresh or refrigerated products and freeze the remainder.

2) Donor human milk

Many hospitals offer pasteurized donor human milk for premature babies when their mothers cannot provide enough colostrum or milk (Boundy 2017). 

3) Infant formula

Lastly, babies may be given specialty or regular infant formula.

Some mothers choose infant formula thinking that it makes premature babies grow faster and allow them to leave hospital earlier. In fact, infant formula-fed babies are more likely to be sick, requiring them to stay in hospital longer.

I) How long to continue supplementing and expressing

Many premature babies leave hospital still needing supplements for a few weeks because they are not yet breastfeeding effectively. These mothers need to keep expressing to provide breast milk for the baby. 

Mothers need to continue expressing after breastfeeding until the baby:

  • Breastfeeds effectively.
  • No longer requires supplements.
  • Is either:
    • At 42 weeks after conception and weighs at least 3,000 gm (6 lb 9 oz).
    • At 44 weeks after conception.

J) Breastfeeding challenges for mothers and getting help

Mothers of premature babies may struggle to establish and maintain their milk supply (Hannan 2018; Hill 2005). They may need to adjust their techniques.

The amount of breastfeeding support provided by hospitals varies, and some health-care providers have limited breastfeeding knowledge (Scime 2018; Yang 2018). Breastfeeding specialists can be very helpful when babies are premature and hospitalized (Mercado 2019).

Consult a health-care provider if:

  • You are unsure of how to establish your milk supply.
  • You are unsure of how to maintain your milk supply.
  • Your expressed amounts are decreasing.
  • It is painful to:
  • Your baby cannot latch.
  • Your nipples are:
    • Damaged.
    • Infected, as this can pose a risk of infection to a very small baby (Kato 2018).
  • You need more support.


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