Abstract: Objective To study whether miRNA is associated with the intrapartum fevers at term in Labor Analgesia. Methods Term cases with or without intrapartum fever after Labor Analgesia, and other cases without receiving Labor Analgesia were recruited. Maternal serum and umbilical vein blood were collected and assayed for interleukin-6 (IL-6) levels. The relative expression of miR-146b、miR-124 and miR-21 were determined by quantitative RT-PCR analysis; 293T cells were transfected with miRNA mimics or control. The effects of miR-146b on IL-6 expression were measured by dual-luciferase assay. The effects of miR-146b on inflammatory signaling pathway were examined by Western blot analysis. Results Maternal and umbilical vein IL-6 levels were higher in intrapartum fevers cases than in controls (median of 145 pg/mL vs 42 pg/mL or 37 pg/ml, p < 0.01). miR-146b expression in both Maternal and umbilical vein was decmiR-146b mimic into 293T cells reduces the reporter gene activity. miR-146b inhibits IL-6/Stat3 signaling pathway in 293T cells. Conclusions miR-146b is associated with the maternal inflammatory response after receiving Labor Analgesia via regulating IL-6 expression.

Key words: Labor Analgesia, miRNA, IL-6, inflammation