Baby Bottle Basics

Who wouldn't love to skip this step when baby's screaming for food in the middle of the night? When you've got a newborn, though, you really shouldn't. Dr. Sears recommends bringing formula or refrigerated breast milk up to body temperature before serving, since very young babies have trouble maintaining their own body temperature. (Never use the microwave, as it can create hot spots in the liquid and alter the properties of both breast milk and formula. Instead, set the bottle or container in a pan of hot water for a few minutes.)

At 4 to 6 months old, however, babies don't care so much about temperature, Dr. Sears says. Some even prefer it straight from the fridge. "My nutty daughter liked her milk cold," says Kristin Arnold Ruyle, a mother in Tampa, Florida. "If it got warm she wouldn't drink it."