Freshly expressed (pumped) breast milk can be safely stored under different conditions for varying lengths of time:

• At room temperature (77°F or 25°C or colder), breast milk is good for up to 4 hours, though some sources note it can remain stable up to 6-8 hours, but 4 hours is generally recommended for best quality and safety

• In the refrigerator (at 39°F or 4°C or lower), breast milk can be stored for up to 4 days according to the CDC and Mayo Clinic. Some sources suggest it may be safe up to 5 days or even 8 days if the fridge temperature is consistently at or below 4°C, but 4 days is the widely accepted guideline

• In the freezer (0°F or -18°C or lower), breast milk is best used within 6 months but can be stored safely up to 12 months. Freezing preserves the milk longer but some nutrient loss can occur over time

• Once thawed in the refrigerator, breast milk should be used within 24 hours and should never be refrozen

• Any leftover milk from a feeding (once the baby has drunk from the bottle) should be used within 1-2 hours or discarded to avoid bacterial contamination

In summary, after pumping, breast milk is good for:

• Up to 4 hours at room temperature
• Up to 4 days in the refrigerator
• Up to 6 months (best) to 12 months (acceptable) in the freezer
• Use thawed milk within 24 hours

Always store breast milk in clean, food-grade containers or specialized breast milk storage bags, label with date/time, and follow safe handling guidelines to maintain quality and safety