Screening and sterilisation processes mean human breast milk can be safely collected and frozen for use at a later time.
Click for a full size image
Breast milk banking continues an ancient human tradition and can save lives
Around 2000 BC breastfeeding was considered a religious obligation.
Now we understand why breast milk is the ideal food for babies, with evidence showing it provides substantial benefits to health even beyond the period of breastfeeding.
The Australian Dietary Guidelines recommend exclusive breastfeeding for around six months, followed by introduction of solid foods and continued breastfeeding. In Australia, over 90% of infants start breastfeeding, and 39% are exclusively breastfed at four months of age.
Although the majority of mothers can breastfeed, some are unable or choose not to. Infant formula is a readily available option. But as the nutritional and developmental value of breast milk becomes better known, more people are trying to source breast milk from another mother.
Breast milk banking provides a safe source of human breast milk in some states in Australia, but greater accessibility is highly desirable.
What’s so good about human breast milk?
The nutritional value of human breast milk is uniquely matched to the needs of human babies. Nutrients such as iron and zinc are provided in a form that is easily absorbed by baby’s immature digestive system and are highly bioavailable; that is, they are in a form that is usable by the body. This ensures nothing goes to waste, and the demands on the mother’s body are minimal.
Specific kinds of fats known as long-chain fatty acids in breast milk are absorbed by the infant, and incorporated into brain and eye tissues.
Breast milk also contains many other valuable bioactive components such as oligosaccharides, immunoglobulins and a molecule called epidermal growth factor.
Oligosaccharides are carbohydrates that are resistant to digestion, remaining relatively intact as they transit through the gut. An example is “bifidus factor”, which acts as a prebiotic (food for bacteria) to promote the growth of the healthy gut bacteria Lactobacillus bifida. Other oligosaccharides stop disease-causing bacteria from attaching to the surface of the gut and urinary tract.
Immunoglobulins are antibodies that help provide immunity, and coat the lining of the gut to prevent attachment of disease-causing bacteria.
Epidermal growth factor stimulates growth and maturity of the infant gut.
What methods have women used to share milk over history?
Wet nursing is a human tradition that has existed for at least 4000 years. It was the only alternative feeding available for babies before the introduction of bottles and formula. Anecdotally, this is still practised in Australia, with sisters or friends with similar aged babies sharing breast feeding.
An increasing trend is informal milk sharing, where mothers seeking breast milk post a request on a dedicated social media page. Examples include Human Milk 4 Human Babies (HM4HB, which has about 4000 Australian members) and Eats on Feets.
Health professionals warn of the small, but real, potential risks of transmission of diseases such as HIV and Hepatitis C through unscreened breast milk. Some donors provide lifestyle information and antenatal blood screening results to recipients, and these are usually private arrangements between individuals.
Women need to be fully informed about the potential risks of using unscreened milk, and balance these with the decision to use formula. Risks associated with formula include a higher incidence of ear infection, gastroenteritis and respiratory infections in infants, and an increased incidence of diabetes, obesity, leukemia, allergy and asthma in later life.
In circumstances where people pay for breast milk, extra caution must be exercised, as there have been reports of dilution of breast milk with water or cow’s milk.
What is a human milk bank, and where are they in Australia?
A human milk bank collects, stores, processes and dispenses donated human milk.
Milk banking was quite common until the 1980s, when the AIDS epidemic sparked concerns about viral transmission through milk. There is now a re-emergence of milk banking in Australia, with five milk banks currently operating;
PREM Milk Bank, Perth
Royal Prince Alfred Hospital, Sydney
Mercy Health Breastmilk Bank, Melbourne
Royal Brisbane and Women’s Hospital Milk Bank, Brisbane
Mothers Milk Bank Pty Ltd, Gold Coast
Who donates breast milk to banks, and how it is processed?
Donors of human milk are often mothers of a premature infant, women who have milk surplus to their needs, or mothers in the community.
Donors undergo rigorous screening, similar to blood donors. Their blood is collected and tested for diseases that could be transmitted through the milk, such as HIV, hepatitis B and C and syphilis. Lifestyle questions related to drug and alcohol use are also used to identify risk of diseases.
Milk is expressed in the donor’s home, or in the neonatal unit (in the case of mothers of a premature infant) under hygienic conditions. It is then frozen for transport to the milk bank. Milk is then thawed, tested for bacterial count and pasteurised, usually using the Holder method, where the milk is heated to 62.5ºC for 30 minutes and then rapidly cooled. The milk is then re-tested for bacterial count, and frozen for dispensing. The combination of freezing and pasteurisation kills harmful viruses and bacteria.
Who can access banked milk in Australia?
Of the five milk banks currently operating in Australia, only the Mothers Milk Bank supplies milk to babies in the community. All other milk banks supply milk exclusively to premature and sick hospitalised infants.
Australian milk banks do not pay their donors, nor can the milk be bought. The cost of milk banks associated with neonatal units is absorbed within the health system. Community milk banks may ask for a donation.
The most recent statistics report there were 7,887 babies who required care in neonatal intensive care units in 2013. Representing 2.6% of all live births, these highly vulnerable infants stand to benefit the most from access to safe human breast milk.
Breast milk protects high risk infants against life threatening conditions such as neonatal sepsis (a dangerous, multi-system infection) and necrotising enterocolitis (a severe disease of the intestine). It has been estimated using donor human milk will provide cost savings of $13 million per year to the Australian health care system by reducing the number of necrotising enterocolitis cases alone.
What happens in states without milk banks?
In Australia, 18 out of 24 neonatal intensive care units do not currently have access to pasteurised donor human milk. As a result, approximately three out of four babies with a high risk of developing necrotising enterocolitis or other neonatal complications do not have access to pasteurised donor human milk.
Although there are significant cost savings linked with preventing necrotising enterocolitis in premature infants on a national basis, the expense of establishing and running a milk bank is often prohibitive for small neonatal intensive care units with relatively low numbers of high risk premature babies.
Recently the Australian Red Cross Blood Service has been considering establishing a national human milk bank, in line with its blood bank service. This would be a welcome adjunct to neonatal units and an important health initiative to improve health outcomes for these vulnerable infants. While this is still in the planning phase, we look forward to hearing more about this possibility soon.
Jacqueline Miller – Senior Lecturer and SAHMRI Fellow, Flinders University
Carmel Collins – Senior Research Fellow and Head of Neonatal Nutrition Research Unit SAHMRI, South Australian Health & Medical Research Institute
This article originally appeared on The Conversation