Brandy Matthews of Albuquerque, NM, was thrilled when her 3-month-old, Addison, started to dribble. "I thought it meant a tooth would pop up soon," she says. But months went by before Addison cut any teeth.

That's because while teething can lead to drooling, it's not the only cause. As your baby tries to put everything in her mouth, her chewing, even without teeth, makes her produce more saliva than she can swallow, says Jennifer Shu, M.D., a pediatrician in Atlanta and coauthor of Heading Home With Your Newborn: From Birth to Reality. Another reason there's extra saliva: Salivary glands are preparing for solid foods.

Your baby will continue drooling until she turns 1. Try to keep her chin and mouth as dry as possible to prevent chafing (though it'll likely be a losing battle). If her skin becomes irritated, soothe it with petroleum jelly.