title: The interplay of the interleukin 1 system in pregnancy and labor.
abstract: This work assessed the temporal coexpression of interleukin 1 (IL-1) and its inhibitor, IL-1 receptor antagonist (IL-1ra), in the cervicovaginal fluid (CVF) beyond 24 weeks gestation including women in spontaneous term labor. Two cohorts of women were recruited at 24 to 35 weeks' gestation (n = 65) and in late pregnancy (>36 weeks' gestation; n = 88). The CVF was serially collected either every 4 weeks between 24 and 35 weeks' gestation (n = 123 samples) or weekly during late pregnancy (n = 240 samples). The IL-1 and IL-1ra were quantitated by enzyme-linked immunosorbent assay, and the effect of vaginal microflora and unprotected sexual intercourse were also investigated. The IL-1β and IL-1ra remain unaltered between 24 and 35 weeks' gestation. At late pregnancy, IL-1α and β concentrations peak at 4 to 14 days prior to labor onset, while IL-1ra decreases with approaching spontaneous term labor (P < .05, 2-way analysis of variance). The IL-1 and IL-1ra were significantly correlated (P < .001, Pearson r). A combined biomarker model of IL-1α, IL-1β, and IL-1ra can predict term labor with 86% sensitivity and 92% specificity. This study indicates a shifting inflammatory balance in the gestational tissues prior to labor onset.
authors.affiliation: 1Department of Obstetrics & Gynaecology, The University of Melbourne, Parkville, Victoria, Australia.
authors.forename: Yujing Jan
authors.initials: YJ
authors.lastname: Heng
authors.forename: Stella
authors.initials: S
authors.lastname: Liong
authors.forename: Michael
authors.initials: M
authors.lastname: Permezel
authors.forename: Gregory E
authors.initials: GE
authors.lastname: Rice
authors.forename: Megan K W
authors.initials: MK
authors.lastname: Di Quinzio
authors.forename: Harry M
authors.initials: HM
authors.lastname: Georgiou
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000378:metabolism; D002584:Cervix Uteri / Q000276:immunology / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005865:Gestational Age; D006801:Humans; D053590:Interleukin 1 Receptor Antagonist Protein / Q000378:metabolism*; D053582:Interleukin-1alpha / Q000378:metabolism*; D053583:Interleukin-1beta / Q000378:metabolism*; D007743:Labor, Obstetric / Q000276:immunology / Q000378:metabolism*; D008137:Longitudinal Studies; D011237:Predictive Value of Tests; D011247:Pregnancy; D015398:Signal Transduction; D047929:Term Birth; D047568:Unsafe Sex; D014621:Vagina / Q000276:immunology / Q000378:metabolism* / Q000382:microbiology
chemical_list: D015415:Biomarkers; C507763:IL1RN protein, human; D053590:Interleukin 1 Receptor Antagonist Protein; D053582:Interleukin-1alpha; D053583:Interleukin-1beta
keywords: cervicovaginal fluid; interleukin-1; interleukin-1 receptor antagonist; labor; pregnancy