To evaluate the potential role of amniotic fluid (AF) interleukin (IL)-6 as a predictor of preterm delivery and to consider possible explanations for the proportion of women with elevated AF IL-6 who deliver preterm yet lack microbiologically detectable intra-amniotic infection.
DATA SOURCES: We searched the English language human literature in MEDLINE, 1966 through September 1999, using the keywords "labor/infant," "premature," "cytokines/interleukin-6," and "AF." We also examined abstracts from the 1999 meetings of the Society for Maternal-Fetal Medicine and the Society for Epidemiologic Research. We identified other studies by reviewing the reference lists of published articles.
METHODS OF STUDY SELECTION: The MEDLINE search yielded 55 citations. We focused on studies that reported on the association between AF IL-6 and preterm delivery.
TABULATION, INTEGRATION, AND
Results
There is consensus in the literature that elevated AF IL-6 is a stronger predictor of preterm delivery than intra-amniotic infection detected by either microbiologic culture or polymerase chain reaction (PCR). Among women with elevated AF IL-6, PCR could detect a higher proportion of intra-amniotic infection than culture. A number of women with elevated AF IL-6 (33-70%) deliver preterm and do not have evidence of intra-amniotic infection by either culture or PCR. Possible explanations for this observation are considered.
Conclusion
Elevated AF IL-6 is strongly associated with preterm delivery and merits future consideration in clinical settings to predict preterm delivery and guide patient care. Development of improved polymerase chain reaction-based clinical methods to detect intra-amniotic infection is necessary to better understand the relationship between elevated AF IL-6, intra-amniotic infection, and preterm delivery.
PMID 10808034 10808034 El-Bastawissi et al. 2000, El-Bastawissi 2000
Cite this article
El-Bastawissi, A. Y., Williams, M. A., Riley, D. E., Hitti, J., & Krieger, J. N. (2000). Amniotic fluid interleukin-6 and preterm delivery: a review. Obstetrics and gynecology, 95(6 Pt 2), 1056-1064.
El-Bastawissi AY, Williams MA, Riley DE, Hitti J, Krieger JN. Amniotic fluid interleukin-6 and preterm delivery: a review. Obstet Gynecol. 2000;95(6 Pt 2):1056-1064.
El-Bastawissi, A. Y., et al. "Amniotic fluid interleukin-6 and preterm delivery: a review." Obstetrics and gynecology, vol. 95, no. 6 Pt 2, 2000, pp. 1056-1064.
Keywords
Amniotic Fluid/chemistry, C-Reactive Protein/analysis, Cytokines/analysis, Female, Humans, Interleukin-6/analysis, Obstetric Labor, Premature/physiopathology, Polymerase Chain Reaction, Predictive Value of Tests, Pregnancy, Sensitivity and Specificity, Cytokines, Interleukin-6, C-Reactive Protein
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