NEW Study Results about Frozen Breastmilk
I just received this email and found it VALUABLE information and wanted to share it ASAP. According to a Breastfeeding Medicine Study, breastmilk that has been thawed up to 8 hours may be refrozen.
NOTE: I have copied and pasted the following email sent to me, therefore it is not my writing I am simply the messenger.
From: Breastfeeding Medicine – Effect of Environmental Conditions on Unpasteurized Donor Human Milk
The following is an excerpt:
“The milk studied was donor milk expressed by mothers who took no special sanitary precautions. The milk was first stored at -20°C (-4°F) for two months and then at -80°C (-110°F) until its use in the experiment. Then the milk was thawed overnight to 4°C (39° F), separated into different sample batches, and refrozen to -80°C (-110°F).
The Study
The second phase of the experiment began by thawing these sample batches of milk to a room temperature of 23°C (73°F). Then each batch was exposed to one of the following conditions:
- 8°C (46°F) for 8 hours
- 8°C (46°F) for 24 hours
- (73°F) for 4 hours
- 23°C(73°F) for 8 hours
- Multiple freeze-thaw cycles of varying lengths
- A steady -20°C (-4°F), considered the control* 23°C
The Results
None of the milk developed unacceptable bacterial counts, the main concern about refreezing milk. In fact, they did not even come close.
There were some changes in vitamin content. Vitamin A levels stayed stable, but vitamin C levels decreased to about one-half when kept at room temperature for 8 hours and by one-fourth when refrigerated for 24 hours. However, the authors note that the reduced vitamin levels are considered adequate for full-term babies and older infants by the National Academy of Medicine.
Differences in fatty acids levels in the milk were considered clinically insignificant and unrelated to repeated freezing and thawing.
The authors write:
“Based on these data, it appears that unpasteurized milk that has been thawed in the refrigerator for up to 8 hours may be safely refrozen. This should allow for. the salvage of milk that mothers might otherwise have been told to discard.”
This study further confirms the robustness of human milk. If its results are replicated, it will also give clinicians another tool to help mothers meet their breastfeeding goals. Then, if due to a power outage or something else, a mother finds herself with a larger amount of thawed milk than her baby can take in 24 hours, she will have the option of refreezing her thawed milk rather than discarding it.
For mothers who express their milk, this information may help them use more and discard less, resulting in better health outcomes for their babies.”
David J. Rechtman, MD, Martin L. Lee and H. Berg, Effect of environmental conditions on unpasteurized donor human milk. Breastfeed Med 2006: 1(1):24-26. doi:10.1089/bfm.2006.1.24.
Available at: http://www.liebertonline.com/
Or: http://www.dors.it/latte/docum/Unpasteurized%20Donor%20Human%20Milk.pdf











Do you know where your readers can find the full-text article for free? The link sends me to a page listing the abstract but in order to read the full-text PDF there is a hefty charge. I also checked PubMed but it’s the same situation. Thanks!
Hello! Unfortunately I do not know where you can find the article for free. However, if you have student or faculty access to research articles via a higher learning institution, this may be included in your subscription. Other than that, I do not know. I just received this email from a lactation consultant and passed on the information!
http://www.dors.it/latte/docum/Unpasteurized%20Donor%20Human%20Milk.pdf
Thanks!!!
[...] Rechtman DJ, Lee ML, Berg H. Effect of environmental conditions on unpasteurized donor human milk. Breastfeed Med. 2006 Spring;1(1):24-6. Also available here. Commentary here: Study results about frozen breastmilk. [...]