3. Prepare your bottle

Sterilize bottles, nipples, caps and rings before using them for the first time. You can sterilize them with any of these methods:

• Boil the bottle and accessories in water for five minutes.
• Use a microwave steam sterilizer bag.
• Use a stand-alone electric steam sterilizer.

After the first use, you usually don't need to sterilize bottles and their parts. Wash these items with soap and hot water. Bottle and nipple brushes can help you clean them well. You also can use a dishwasher.

You might continue sanitizing the bottle if your baby:

• Is younger than 3 months.
• Was born prematurely.
• Has a weakened immune system.