I had to post and run before. This is from the La Leche League's website.
All milk should be dated before storing. Storing milk in 2-4 ounce amounts may reduce waste. Refrigerated milk has more anti-infective properties than frozen milk. Cool fresh milk in the refrigerator before adding it to previously frozen milk.
Preferably, human milk should be refrigerated or chilled right after it is expressed. Acceptable guidelines for storing human milk are as follows. Store milk:
- at room temperature (66-78°F, 19-26°C) for 4 hours (ideal), up to 6 hours (acceptable) (Some sources use 8 hours)
- in a refrigerator (<39°F, <4°C) for 72 hours (ideal); up to 8 days (acceptable)
- in a freezer (-0.4 to -4°F, -18 to -20°C) for 6 months (ideal) up to 12 months (acceptable)
Previously frozen milk that has been thawed can be kept in the refrigerator for up to 24 hours. While there is limited evidence to date that milk thawed for a few hours may be refrozen, this results in further breakdown of milk components and loss of antimicrobial activity. At this time, the accepted practice is not to refreeze thawed milk. While some mothers and caregivers reheat expressed milk that was leftover and refrigerated after a previous feeding, there is no research on the safety of this practice. There is also no research about whether freshly expressed milk left unfinished at room temperature should be discarded, or can be saved for a short time (perhaps up to one hour as reported by some mothers and caregivers) to finish the feeding
if the baby wakens from having fallen asleep or still appears hungry. According to THE BREASTFEEDING ANSWER BOOK, page 228, research indicates that human milk has previously unrecognized properties that protect it from bacterial contamination