Inflammation of the womb is known to cause spontaneous pre-tem labor. Bacteria is often a suspected cause, but doctors have been stymied trying to find the bacteria responsible. Cultures of the amniotic fluid - the gold standard for finding bacterial infections - often come back negative.
This has long perplexed researchers, explains Yi Ping Han, a microbiologist at Case Western School of Dentistry. Han says the problem is that the traditional culture technique only picks up a small fraction of bacteria that might be responsible for an infection.
HAN: More than 99 percent of bacteria in the environment are uncultivated - that is we cannot grow them in the laboratory. We don't know what they require to grow.
What this means is that diagnoses that rely on bacterial cultures are missing A LOT . So Han and her colleagues decided to take a different tack. Instead of trying to grow bacteria, they looked for the bacterial DNA. Not only did the samples come back positive for a common bacteria in the mouth, they contained multiple species of harmful bacteria, some of which had not been previously linked with pre-term birth.
One of the bacterial species they found, called fusobacterium nucleatum, is common in periodontal disease - and earlier research by Han's group has shown that once in the bloodstream it can lead to uterine infections, early labor, and miscarriage.
Han says the bacteria are very common, and they're still not sure why it leads to infection in some women but not in others. But she has some advice.
HAN: Maintain good oral health before and during pregnancy - so always brush , floss, and all that …
Because reducing the number of bacteria in your mouth, Han says, reduces the risk they might harm your baby.
Gretchen Cuda, 90.3