Letter to the Editor
The article on drugs affecting milk supply during lactation states that babies drink 150 mL/kg/day.1 This calculation is used for newborns and for formula-fed babies, but is not applicable to breastfed babies past the early days. Research from the Hartmann Human Lactation Research Group at the University of Western Australia showed that from one month until six months of age, babies drink on average 800 mL/day.2 The amount varies only minimally with age and weight, contrary to previous belief, although the average intake from baby to baby can vary from 500 mL to 1350 mL/day. At six months when solid foods are normally introduced, this amount gradually reduces.
It is misleading to report that mothers in general need to produce 1350 mL/day, when this is at the very upper limit determined from the Hartmann study and a volume that would be consumed by very few babies.
Please could you correct this information? Fully referenced amounts are available on the Australian Breastfeeding Association website.3
Letter to the Editor
Thank you for the article on drugs affecting milk supply in lactation.1 This area is of particular interest to me as a community pharmacist and a breastfeeding mother myself. I enjoyed the article and it was relevant to many of the situations that I come across in the community.
I did notice that some of the information about milk supply differs from the current Australian Breastfeeding Association guidelines. The article states that maintaining the milk supply may be problematic as the baby grows. An infant typically requires 150 mL/kg/day. So, to feed a 9 kg versus a 3 kg baby daily (1350 mL vs 450 mL) can be a physiological challenge for some women. While I have seen references to 150 mL/kg/day used, most conclude that milk intake of exclusively breastfed infants averages 750–800 mL/day, but can vary from less than 500 mL to more than 1000 mL/day.
My current understanding is that the volume of breastmilk consumed is typically consistent from one to six months of age.2 I would also add that in my experience, it is extremely uncommon for mothers to successfully establish breastfeeding then be physiologically challenged to produce enough milk as their baby grows, if they have been advised to feed according to their baby’s needs without supplementing with formula or solid food.
Is there a reference to support mothers being physiologically challenged as their babies get older?
- McGuire TM. Drugs affecting milk supply during lactation. Aust Prescr 2018;41:7-9.
- Kent JC, Mitoulas LR, Cregan MD, Ramsay DT, Doherty DA, Hartmann PE. Volume and frequency of breastfeedings and fat content of breast milk throughout the day. Pediatrics 2006;117:e387-95.
- Exclusive expressing. Melbourne: Australian Breastfeeding Association; 2017. [cited 2018 May 1]
- World Health Organization, UNICEF. Breastfeeding counselling: a training course. WHO/CDR/93.3-5. Geneva: WHO; 1993. [cited 2018 May 1]
- Reilly JJ, Ashworth S, Wells JC. Metabolisable energy consumption in the exclusively breast-fed infant aged 3--6 months from the developed world: a systematic review. Br J Nutr 2005;94:56-63.
- Kent JC, Mitoulas LR, Cregan MD, Ramsay DT, Doherty DA, Hartmann PE. Volume and frequency of breastfeedings and fat content of breastmilk throughout the day. Pediatrics 2006;117:e387-95.
- Kent JC, Hepworth AR, Sherriff JL, Cox DB, Mitoulas LR, Hartmann PE. Longitudinal changes in breastfeeding patterns from 1 to 6 months of lactation. Breastfeed Med 2013;8:401-7.
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