Frozen Assets: The secret life of expressed breastmilk

Your breasts are capable of producing enough milk for your baby - or babies! Twins, triplets and even quads can be exclusively breastfed. (Perhaps even more but there are only so many hours in a day!)

So why do most women struggle to pump extra milk on a regular basis to donate or store in their freezer?

Breastmilk production is established in the early days. The amount of milk being regularly removed sets the ongoing production rate. Once established, the supply is then maintained.

Mothers of premature babies are often pumping larger volumes of milk compared to the tiny volumes of their tiny babies stomachs. It might be months before their baby catches up and the supply regulates to the baby's intake. Sometimes they maintain high production even once direct feeding begins.

Other mothers whose babies have challenges learning to attach might be expressing frequently to protect their supply and could also be removing more milk than their baby requires.

When mothers are removing large volumes during the early days, they sometimes program their production to a higher level than if their baby was regulating their supply. If they maintain that high production by regularly expressing in addition to direct breastfeeding, their breasts will maintain the artificially high production. Basically, breasts make what they are told to make. Enough milk for more than one baby? Okay!

Peer Pressure

You see a lot of photos on social media, freezers packed with frozen breastmilk. Some of these mothers might be exclusively pumping and have a stockpile from the early days they are maintaining. Some women intentionally maximise production beyond their baby’s needs, so they can donate breastmilk. Some people enjoy the challenge of building a freezer stash without actually needing the milk and might discard it if nobody wants it.

Fresh from the breast is the way nature planned it. Freezing breastmilk does impact its composition and the longer it is stored, the greater the effect. Frozen breastmilk should be clearly labelled with the date of expression and the oldest milk should be used first. Guidelines for storage should be followed and long-term storage depends on the type of freezer and where the milk is positioned.

Finding the Facts

Guidelines for human milk storage are largely based on general food safety recommendations. However, breastmilk is a living fluid with its own microbiome. Research is currently underway by the Geddes Hartman Human Milk Research Group at he University of Western Australia (UWA) looking at the impact of cold storage on breastmilk.

Freeze-dry your breastmilk?

Commercial enterprises in the USA are marketing services to freeze dry your own breastmilk, claiming to extend storage to three years! Your breastmilk is sent to their facility, processed and returned to you in a powdered form which doesn't require cold storage.

The comodification of breastmilk as a consumable has increased in the US in recent years. With no paid maternity leave, many mothers have no choice but to return to work within days or weeks after birth. Pumping breastmilk partly or completely replaces direct feeding for many of these mothers.

Breastfeeding is more than just the milk. It is a relationship between a baby and their mother. It is also a relationship between the baby and the breasts. Direct feedback from the baby is key to many aspects of lactation, including the seeding of the infant microbiome by the mother. Breastmilk also signals the baby as it changes throughout the day and night, from day to day and week to week. From hormones which regulate day and night to an immediate response to bacteria and viruses in the baby's mouth, direct feeding is very different to expressed breastmilk feeding.

While it is important that milk can be expressed and stored for babies who cannot always be fed at their mother's breast, it is important that we do not devalue the role of breastFEEDING by following the American example of normalising pumping and idealising expressed breastmilk.

Buying and selling human milk?

Breastmilk should not be a commodity to be marketed. The US allows the sale of human milk, which is an illegal practice in Australia and many other countries. Online sales platforms like EBay prohibit the sale of human milk. Breastmilk is a baby’s birthright and there is a risk that impoverished women can sell their milk at a profit while feeding their infant’s free or subsidised infant formula.

Perhaps even more alarmingly, there is a blackmarket trade where human breastmilk is being sold to a market including body builders and cancer patients. Unregulated, this milk can be diluted or even substituted with cow or other milk. Whilst a harmless, if expensive, con of adults if a baby was fed the end result it could lead to illness or death.

In just a few decades, expressing breastmilk has gone from a mostly private process to remove small volumes of milk to relieve pressure or feed a baby born prematurely to a multi million global market of breast pumps and assorted accessories and the sale of the very milk itself.