The aim of this study was to investigate the association between the fetal inflammatory response (FIRS) and pathological changes in placenta as well as the characteristics of the perinatal period in preterm delivery.
The object and methods of investigation. A prospective random sampling was performed at Vilnius City University Hospital in 2007-2010. 158 preterms, born at the 22-34 weeks of gestation, and their mothers have been investigated. Umbilical blood cord cytokines were studied and placental patologohistological tests were evaluated. Depending on the concentration of IL-6 cytokine in the umbilical blood cord, the people under investigation were divided into two groups: FIRS (IL-6 ≥ 11 pg/ml) group (n = 52) or control (IL-6 < 11 pg/ml) (n = 106). The evidence of clinical, laboratory and instrumental tests in the perinatal period for all mothers was selected and evaluated. The risk factors for the incidence of FIRS were determined. The statistical data analysis was carried out.
Results. The period of gestation in both groups was significantly different (p < 0,001). In FIRS group the women most often gave birth at 31-32 (2.8%) or 24-26 (21.2%) weeks of gestation, while women from the control group – at 33-34 weeks of gestation (58.5%). In FIRS group the average waterless period at labour was 26.81h, while in the control group it was only 16.73 h. The waterless period ≥18 h in FIRS group was found to occur twice as often as in the control group (p < 0.05). The average body temperature in women from the FIRS group was found to be significantly higher (p < 0.05). The higher incidence of postnatal endometritis in this group was also detected (p < 0.05). Histological chorioamnionitis and funisitis were detected in 51% of placentas from the FIRS group, while in the control group we found only 1% (p < 0.001). Histological tests performed on placentas expressing infectional inflammation more correlated with the concentrations of IL-6 and bTNF-α in umbilical blood cord (p < 0.001).
Conclusions. Histologically confirmed chorioamnionitis is a significant marker for a higher incidence of FIRS. A shorter than 30 week pregnancy, waterless period at labour ≥18 h and body temperature before giving birth ≥37°C as well as postnatal endometritis, – all these are the factors significantly increasing the FIRS incidence.
Keyword(s): fetal inflammatory response, cytokines, preterm delivery, intrauterine infection, chorioamnionitis.
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