Jan 28, 2011 10:54 GMT  ·  By

A new research carried out by scientists from Harvard Medical School, Brigham and Women's Hospital and Children's Hospital of Boston, concluded that the bacteria that colonizes the placenta during pregnancy could be linked to preterm birth and other developmental problems in newborns.

In the United States, preterm births occur in almost half a million pregnancies, and despite improved care, preterm and extremely low-gestational-age newborns are at a considerably higher risk of morbidity, mortality and developmental problems.

Most of these issues are caused by an imbalanced inflammatory response of the fetus and the newborn.

The researchers explain that “the fetal inflammatory response appears to contribute to the onset of preterm labor, fetal injury and complications, underlying lifetime health challenges facing these children.

“Our data suggest that placental colonization by specific groups of organisms can increase or decrease the risk of a systemic inflammatory condition.”

To better understand the role that these microorganisms play in these extreme inflammatory responses, the scientists carried out an analysis of the protein biomarkers in dry blood spots gathered from 527 newborns, delivered by C-section.

They cultured and identified the bacteria from their respective placentas, and found that the placentas that were primarily colonized by microorganisms associated with bacterial vaginosis (BV), belonged to newborns who had high levels of proinflammatory proteins.

On the other hand, placenta colonization by Lactobacillus species of bacteria were associated with lower levels of proinflammatory proteins.

One of the authors of the study, Andrew Onderdonk of Harvard Medical School and Brigham and Women's Hospital, says that this “study supports the concept that the placental colonization with vaginal microorganisms can induce a systemic inflammatory response in the fetus and newborn and that the dominating molecular feature of this response can be dependent on the type of bacteria.”

The systemic fetal inflammatory response to intrauterine infections is responsible for lifelong consequences of preterm labor, fetal injuries and early organ damage.

Nearly half of all placentas delivered before the second trimester and 41% of those delivered by C-section, contain microorganisms that are detectable by culture techniques.

“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,” Onderdonk added.

These findings are published in the current issue of the online journal mBio.