Certain kinds of bacteria that colonize the placenta during pregnancy appear to be associated with preterm birth and other developmental problems in newborns, according to microbiologists writing in the journal mBio.
Fetal inflammatory response leading to preterm birth and other problems appears to be linked to placental colonization by specific groups of organisms that can increase or decrease the risk of a systemic inflammatory condition, explain the researchers.
"Our data suggest that preterm birth occurs in nearly a half million pregnancies in the United States alone. Much of this risk is attributable to imbalanced inflammatory responses of the fetus and newborn," the article notes.
Approximately half of all placentas delivered before the second trimester and 41 percent of those delivered by Caesarean section harbor microorganisms detectable by culture techniques.
To better understand what role these microorganisms could play in the preterm inflammatory response, the researchers analyzed protein biomarkers from 527 newborns delivered by Caesarean section and cultured and identified the bacteria from their respective placentas.
The researchers found that the placentas colonized by microorganisms commonly associated with the condition know as bacterial vaginosis were found to be associated with elevated levels of proinflammatory protein in newborns. In contrast, colonization by Lactobacillus species of bacteria (often found in decreased concentrations in cases of bacterial vaginosis) were associated with lower levels of proinflammatory proteins.
"Our study supports the concept that the placental colonization with vaginal microorganisms can induce a systemic inflammatory response in the fetus and that the dominating molecular feature of this response can be dependent on the type of bacteria," says Andrew Onderdonk of Harvard Medical School, one of the authors of the study. "Our data suggest that the targeting of placental colonization by specific drugs or probiotics during early pregnancy may hold promise for preventing not only preterm birth but also the devastating and far-reaching inflammatory consequences in premature newborns."
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Source: American Society for Microbiology