Medical professionals believe that expectant mothers could reduce the risk of complications in their pregnancies and newborn babies by paying closer attention to oral hygiene.
Researchers from Queen Mary University, London, found that bacteria from a mother's mouth can find their way into the amniotic fluid and blood in the womb, which could lead to complications including premature onset of contractions and delivery, as well as infection or low birth weight in a newborn child.
Speaking at the Society for General Microbiology in Harrogate today, Queen Mary University's Cecilia Gonzales-Marin said that better oral hygiene could reduce these risks.
Ms Gonzales-Marin's study tested the stomach contents of 57 newborn babies and identified 46 different types of bacteria.
Two of these, Granulicatella elegans and Streptococcus sinensis, were bacteria normally found in the mouth and are known to be able to enter the blood. They are associated with infections such as infective endocarditis.
Ms Gonzales-Marin said: 'Our research group is using DNA techniques to confirm if bacteria from the newborn matches the bacteria in the respective mother's mouth.'