Significantly different microbiomes were seen in the reproductive tracts of pregnant women who had a baby born prematurely vs. women who delivered full term. Findings from the study are published in the Proceedings of the National Academy of Sciences.

Researchers from the March of Dimes Prematurity Research Center at Stanford University obtained weekly samples of the microorganisms from the teeth, gums, saliva, reproductive tract, and stool from pregnant women (n=49). For each woman, little change was seen in the microbiome on a weekly basis at each location. However, study authors noticed differences in the reproductive tracts for women who delivered their babies too early vs. those who delivered full term. These differences were detected early in the pregnancies and persisted throughout the pregnancies.

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Also, the microbiome patterns changed right after the baby’s delivery and did not revert back to pre-pregnancy patterns for at least a year in some women. This may explain why women with closely spaced pregnancies have a higher risk of preterm birth, researchers noted.

The findings may help in screening women to detect and predict those who are more likely to have a premature delivery.

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