When should breast milk be discarded?

• A. After one week in the refrigerator
• B. If it has been left out at room temperature for over 4 hours
• C. After two hours at room temperature
• D. If it has been partially thawed

Answer: (B)

Breast milk should be discarded if it has been left out at room temperature for over 4 hours because bacteria can grow in breast milk when it is not properly stored. The general guideline is that breast milk can be safely left at room temperature (around 77°F or 25°C) for up to 4 hours. After this period, the risk of bacterial growth increases, making it unsafe for consumption. This guideline helps to ensure that the milk remains safe and nutritious for the baby.

In the context of the other options, while breast milk has specific storage timeframes, the critical factor in this case is the temperature aspect. For example, the maximum safe refrigeration time is longer than one week, and partially thawed milk can often be re-frozen or used as long as it hasn’t been left out too long, which differs from the situation of milk left out at room temperature. Therefore, adhering to the 4-hour rule is essential for maintaining the safety of the milk for the baby.