Subclinical chorioamnionitis as an etiologic factor in preterm deliveries

Objective: This study was performed to determine the possible relationship between histologic chorioamnionitis and genital tract cultures and their co ntribution to preterm delivery. Methods: The study group consisted of 45 pr eterm and 37 term pregnancies. Cervico-vaginal cultures were obtained from all patients at admission and placentas were histopathologically evaluated and graded for inflammation of the chorial plate, amniochorionic membrane, umbilical cord and villi. Inflammation scores and presence of pathogenic ba cteria were compared between the preterm and term patients. Results: Severe chorionic plate inflammation was present in 35.5% of 45 preterm deliveries as compared to 5.4% of 37 term deliveries. Amniochorionic-decidual inflamm ation was not present in 14 of the term deliveries (38%), mild (Grade 1-2) in 20 (54%) and severe (Grade 3-4) in 3 (8%) as compared to 14 (31%), 17 (3 8%), and 14 (31%) in the preterm group, respectively (P < 0.05). Pathogenic bacteria were isolated from the lower genital tracts of all patients who h ad severe chorionic plate (CP) and/or chorioamnionic (CA) inflammation whil e this was true only in 37.5% of the patients with no or only mild chorioni c plate inflammation (P < 0.001 for CP, P < 0.01 for CA). Conclusion: Our r esults show that pathogenic bacterial colonisation of the cervicovaginal re gion is closely associated with placental inflammation, preterm labor and c ervico-vaginal cultures which may be useful in determining the pregnancies at risk for preterm labor. (C) 2001 International Federation of Gynecology and Obstetrics. All rights reserved.