Objective: To study whether interleukin-8 (IL-8) mRNA in vaginal secretions is associated with congenital infection and preterm delivery in the case of preterm labor with intact membranes.
Methods: This prospective clinical study in a tertiary referral center included 280 patients who gave birth to 360 infants from 1997 through 1999. IL-8 mRNA in vaginal secretions was determined with reverse transcriptase polymerase chain reaction. Logistic regression was used to examine the association between vaginal IL-8 mRNA and congenital infection independently of the time of birth. Main outcome measures were congenital infection and delivery before 37 and 33 weeks' gestation.
Results: A total of 100 women (100/280 (35.7%)) gave birth before 37 weeks. A total of 54 children (54/360 (15%)) had congenital infection. IL-8 mRNA in vaginal secretions was associated with delivery within 14 days of the sampling (24 (15.6%) vs. 7 (5.6%) p < 0.01), but not with delivery within 48 h, 7 days (p = 0.07) or before 37 or 33 weeks. There were more congenital infections in the group with detectable IL-8 mRNA (37 (19.3%) than in the negative group (17 (10.1%); p < 0.05). IL-8 mRNA was associated with congenital infection independently of the time of birth (OR: 2.6 (1.3-5.1)). This test had a sensitivity for predicting neonatal infection of 69%. Its specificity was 49%, its positive predictive value 19%, and its negative predictive value 90%.
Conclusion: IL-8 mRNA could be a prenatal noninvasive vaginal marker of congenital infection.
Copyright 2004 John Wiley & Sons, Ltd.