Doctors may soon be able to determine whether a pregnant woman will give birth prematurely using just a mouth swab.
Scientists have discovered that bacteria in the placenta contains clues about whether a pregnancy will reach full term or whether a baby will arrive early.
Researchers, led by Dr. Kjersti Aagaard at the Baylor College of Medicine and Texas Children's Hospital, studied the placentas of 320 women, some of whom had delivered prematurely (at 34-37 weeks) and some of whom had reached full term.
They analysed the placentas within an hour of delivery and discovered that the microbes present in the placentas differed between those in the premature and those in full term groups.
Dr Aagaard said that it is not yet known whether these differences cause premature births, but the association is strong enough to make it worth studying further.
She believes that the varying communities of bacteria could affect both the placenta's ability to nurture the baby and the baby's development.
According to Time.com, Aagaard says that even if a specific bacterial composition in the placenta appears to cause early delivery, it is not practical nor safe to sample the placenta throughout pregnancy to find out.
A safer option would be sampling the bacterial makeup in the mouth, which are similar to those in the placenta, suggesting that in the future, a mouth swab may provide the same information.
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