Gum or periodontal disease is caused by a chronic bacterial infection and can lead to bone loss, damaged gum tissue and even tooth loss. However, even more frightening is the fact that a new study suggests that gum disease may also increase the risk of preterm birth, and it is not the first time this association has been made. Overall, studies have concluded that the increased risk is anywhere from 3 to 8 times as great.

Preterm birth is an important cause of illness in American infants and often results in long-term damage such as neurological disability.

Although studies in animals and humans have suggested that infections in general can be a cause of preterm birth, it is not entirely clear why gum disease contributes to preterm birth. However, mouth infections cause inflammation, which is associated with a number of naturally occurring factors, such as prostaglandins and cytokines.

The biological mechanism is still being studied, but it has been shown that periodontal infections in animals impair fetal growth. This impaired growth is believed to be due to the enhanced release of cytokines, such as prostaglandin and tumor necrosis factor. These same substances have been shown to elicit preterm delivery in humans (Journal of Periodontology 1996; 67[10 suppl]:1103-1113).

Because of this effect, prostaglandin-like drugs are often used in obstetrics to induce labor or help it progress. So, given how closely related these drugs are to the body's own prostaglandins, it makes sense that infections involving severe inflammation could be associated with preterm birth.

This study found that the worse the gum disease was, the more likely a woman was to have a preterm birth. One of the researchers suggests that women contemplating pregnancy and those already pregnant "should ask their dentist to examine them for periodontal disease."

Annual Meeting of the American Association for Dental Research June, 2000