For at least the first four months, sterilize the equipment you use to mix your baby’s infant formula.
You will need:
Put the bottle in a container of hot water for a few minutes, or hold it under warm, running tap water. Test the temperature by putting a few drops on your wrist.
Warming infant formula or baby food in the microwave can be risky. Microwaves can cause "hot spots" that could burn your baby’s mouth. Some babies have been so seriously scalded that they needed treatment in a hospital. The hot spots can develop even when the bottle feels cool to the touch. Some plastic bottle liners break if their contents become too hot. Therefore, many baby experts recommend against using the microwave oven to warm a baby’s formula.
Some parents choose to use the microwave oven anyway. If you do use your microwave oven to warm your baby’s formula, follow these guidelines: