An elevated amniotic fluid prostaglandin F_2αconcentration is associated with intra-amniotic inflammation/infection, and clinical and histologic chorioamnionitis, as well as impending preterm delivery in patients with preterm labor and intact membranes

Abstract

Objective To determine whether an elevated amniotic fluid concentration of prostaglandin F2α (PGF2α) is associated with intra-amniotic inflammation/infection and adverse pregnancy outcomes in patients with preterm labor and intact membranes. Materials and Methods The retrospective cohort study included 132 patients who had a singleton pregnancy with preterm labor (<35 weeks of gestation) and intact membranes. Amniotic fluid was cultured for aerobic and anaerobic bacteria as well as genital mycoplasmas. Intra-amniotic inflammation was defined by an elevated amniotic fluid matrix metalloproteinase-8 (MMP-8) concentration (>23 ng/mL). PGF2α was measured with a sensitive and specific immunoassay. The amniotic fluid PGF2α concentration was considered elevated when it was above the 95th percentile among pregnant women at 15–36 weeks of gestation who were not in labor (≥170 pg/mL). Results (1) The prevalence of an elevated amniotic fluid PGF2α concentration was 40.2% (53/132) in patients with preterm labor and intact membranes; (2) patients with an elevated amniotic fluid PGF2α concentration had a significantly higher rate of positive amniotic fluid culture [19% (10/53) vs. 5% (4/79); p = 0.019], intra-amniotic inflammation/infection [49% (26/53) vs. 20% (16/79); p = 0.001], spontaneous preterm delivery, clinical and histologic chorioamnionitis, and funisitis, as well as a higher median amniotic fluid MMP-8 concentration and amniotic fluid white blood cell count and a shorter amniocentesis-to-delivery interval than those without an elevated concentration of amniotic fluid PGF2α (p < 0.05 for each); and (3) an elevated amniotic fluid PGF2α concentration was associated with a shorter amniocentesis-to-delivery interval after adjustment for the presence of intra-amniotic inflammation/infection [hazard ratio 2.1, 95% confidence interval (CI) 1.4–3.1; p = 0.001]. Conclusion The concentration of PGF2α was elevated in the amniotic fluid of 40.2% of patients with preterm labor and intact membranes and is an independent risk factor for intra-amniotic inflammation/infection, impending preterm delivery, chorioamnionitis, and funisitis.

Are amniotic fluid neutrophils in women with intraamniotic infection and/or inflammation of fetal or maternal origin?

“…Interestingly, in all of the cases, Ureaplasma urealyticum was found in the amniotic cavity by conventional microbiological techniques or live/dead staining. This genital mycoplasma was either found to be alone or associated with Mycoplasma hominis , both of which are associated with spontaneous preterm labor and birth 32, 62, 63, 78, 79, 99-104 and/or clinical chorioamnionitis 73, 104 , both regarded as major clinical pregnancy complications 105-115 . Genital mycoplasmas can induce severe inflammatory responses in the amniotic cavity and surrounding tissues 116-120 , which may be characterized by the migration of maternal neutrophils into this compartment, as demonstrated herein.…”

The Human Ureaplasma Species as Causative Agents of Chorioamnionitis

“…These inflammatory cytokines and chemokines stimulate PG production (63,64) and neutrophil infiltration and the release of MMPs (65), thus leading to cervical ripening and weakening/rupture of the fetal membranes. Indeed, the levels of MMPs (66) and PGs (56,67) are significantly increased within the amniotic fluid and fetal membranes during chorioamnionitis.…”

Clinical chorioamnionitis at term VII: the amniotic fluid cellular immune response

“…The intra-amniotic inflammatory response is characterized by an increased amniotic fluid white blood cell count [33–37] and increased concentrations of inflammatory mediators, such as cytokines [27, 34–36, 38–75] and prostaglandins [76–85]. However, there is a paucity of information about the cellular composition of the intra-amniotic inflammatory response in clinical chorioamnionitis, and most studies have reported changes in the total white blood cell count of the amniotic fluid while using a hemocytometer chamber (e.g.…”