Sucking habits outside of breast-feeding, such as using pacifier, baby bottle, or finger sucking may have detrimental effects on speech development in young children.

A study that took place in Patagonia, Chile, found that pre school children with persistence of these sucking habits were more likely to have difficulty producing certain word sounds and to simplify their pronunciation.

Researchers gathered parents from 128 children age 3 years to 5 years and collected their reports of each child's sucking and feeding method during infancy and evaluated the child's speech. They found that delaying using a baby bottle until the child was at least 9 months old could reduced the risk of later developing speech disorders, while children who used a pacifier or who sucked their fingers for more than 3 years were three times more likely to develop speech impediments.

This results provide further evidence for the benefits of longer duration of breast feeding of infants and suggest that extended sucking outside of breast-feeding may have detrimental effects on speech development in young children.

Breast-feeding is still the best method for feeding infant. Previous research also has suggested that breast feeding may be beneficial to developing coordinated breathing, swallowing and speech articulation.