ABSTRACT
In this study we evaluated different markers of infection and their relationship to
preterm delivery. Forty-four consecutive women with singleton pregnancies in uncomplicated
preterm labor were investigated. C-reactive protein (CRP) in peripheral maternal blood,
amniotic fluid cytokines, amniotic fluid leukocyte count, and amniotic fluid culture
were performed in all patients. Thirty-six patients responded to standard tocolytic
therapy and delivered after 34 weeks' gestation. In eight patients treatment failed
and they delivered before 34 weeks' gestation. Two of these eight patients had a positive
amniotic fluid culture for Ureaplasma urealyticum. The positive culture was accompanied by an elevated neutrophil count in the amniotic
fluid. Elevated amniotic fluid levels of tumor necrosis factor (TNF) (more than 23
pg/mL), interleukin-6 (IL-6) (more than 2292 pg/mL) and interleukin-8 (more than 164
pg/mL) correlated with early preterm delivery. CRP levels in serum had a low sensitivity
(38%) but a high specificity (94%) in predicting preterm delivery. This study indicates
that preterm labor can be initiated by infection. Markers of infection obtained by
amniocentesis have a better sensitivity and positive predictive value than noninvasive
markers. Elevated IL-6 (more than 2292 pg/mL) seems to be the best predictor for preterm
delivery, with a sensitivity of 75% and a specificity of 97%.
Keywords
Infection - preterm delivery - amniocentesis - interleukin-6 -
Ureaplasma urealyticum
