Colonization of second-trimester placenta parenchyma

Abstract

Objective-The overtly healthy, non-pregnant uterus harbors bacteria, Mycoplasma and Ureaplasma. The extent of colonization remains elusive, as are relationships between isolated microorganisms, preterm labor and fetal inflammation.Study Design-Biopsies of chorion parenchyma from 1083 placentas delivered before the beginning of the 28 th week of gestation were cultured, and the placenta was examined histologically. The frequencies of individual microorganisms and groups of microorganisms were evaluated in strata of processes leading to preterm delivery, routes of delivery, gestational age, and placenta morphology Results-Placentas delivered by cesarean section with preeclampsia had the lowest bacterial recovery rate (25%). Preterm labor had the highest rates, which decreased with increasing gestational age from 79% at 23 weeks to 43% at 27 weeks. The presence of microorganisms in placenta Conclusions-The high rate of colonization appears to coincide with phenomena associated with preterm delivery and gestational age. The presence of microorganisms within placenta parenchyma is biologically important.

Reduced mortality and increased BPD with histological chorioamnionitis and leukocytosis in very-low-birth-weight infants

“…Bacterial invasion of the umbilical cord has been associated with increased rate of microorganism recovery in the placenta. 18 In support of this finding, infants in our study sample with funisitis had an increased occurrence of leukocytosis. Neutrophils and other WBCs are important components of host defense.…”

“…The rate of early onset culture proven sepsis was low in our study sample but, as our study included only those infants exposed to histological chorioamnionitis, risk of subclinical bacterial infection was likely high. As histological chorioamnionitis frequently accompanies premature birth, 17 and may be indicative of exposure to multiple microorganisms, 18 a robust inflammatory response may be important in preventing more systemic bacterial infection, thus decreasing the risk of mortality. Bacterial invasion of the umbilical cord has been associated with increased rate of microorganism recovery in the placenta.…”

The Human Microbiome during Bacterial Vaginosis

“…There is evidence that immune responses to BV bacteria ascending into the upper reproductive tract and colonizing the placenta can cause inflammation, with an impact on newborn health. Using culture-based techniques, Onderdonk et al showed that vaginal bacteria can ascend and frequently colonize the preterm placenta during pregnancy (127). Others have confirmed the presence of bacteria in the placenta by using histology and molecular techniques (128,129).…”

SExual Epigenetic Dimorphism in The Human Placenta: Implications for Susceptibility During The Prenatal Period

“…The tissue was placed into a cryo vial and immediately immersed in the liquid nitrogen. Specimens were stored at -80°C until laboratory processing [38].…”