A POSSIBLE IMMUNO-MODULATORY ACTION FOR CERVICAL CERCLAGE IN WOMEN AT RISK FOR PRETERM LABOR

Objectives: To estimate and evaluate changes in cervico-vaginal fluid (CVF) content of interleukin (IL) 6 and 18 and granulocyte macrophage- colony stimulating factor (GM-CSF) in pregnant women with past history of preterm birth (PTB) underwent prophylactic cervical cerclage (CC), or vaginal progesterone (VP) or both. Patients & Methods: Baseline TVU was performed for estimation of cervical length (CL) and women had CL >25 were considered as Control group and women had CL<25 mm were divided into three groups according to provided prophylactic therapy, A, B and C, respectively. At the 24th week (24-wk) gestational age (GA), CVF samples were obtained for ELISA estimation of levels of IL-6, IL-18 and GM-CSF and repeated with estimation of CL at 30-wk GA. Frequency of PTB and the effect of applied therapeutic lines on CVF levels of studied cytokines were determined. Results: At 24-wk, 27 women had CL>25 mm and 169 women had CL<25 mm, at 30-wk CL was significantly shorter in study than control women. Seven control and 46 study women had PTB prior to 34 wk with significantly higher frequency in group B than group C. At 24-wk, IL-6 levels were significantly higher, while IL-18 and GM-CSF levels were non-significantly higher in study versus control women. At 30-wk, IL-6 and GM-CSF levels significantly decreased in groups A and C, while increased in group B than their 24-wk levels with significant difference versus other groups. At 30-wk, IL-18 levels decreased significantly than 24-wk levels with non-significant inter-group differences. Duration of pregnancy showed negative significant correlation with CL%, but positive significant correlation with extent of decrease in cytokine levels. Percentage of decrease of studied cytokines and duration of pregnancy showed positive significant correlation with taking CC as line of management. Statistical analyses defined CL% as negative predictor and the extent of decreased IL-6 levels was the only significant positive predictor among studied cytokines. Conclusion: Disturbed local immune milieu towards increased pro-inflammatory cytokine production plays a role in pathogenesis and acceleration of PTB. CC induced down-regulation of inflammatory cytokines production and allowed prolongation of duration pregnancy; thus CC works beyond its mechanical preventive effect.