AbstractIntroductionTo explore the role of IL‐6/JAK/STAT signaling in tubal infertility.MethodsThe fimbriae tissues of 14 patients with a history of infertility and hydrosalpinx and 14 patients with no history of infertility and no fallopian tube disease were collected. The tissues were then divided into hydrosalpinx group and control group followed by analysis of the protein expression of key factors in the IL‐6/JAK/STAT signaling by immunohistochemistry and Western blot.ResultsImmunohistochemical staining showed significantly higher level of IL‐6, JAK1, p‐JAK1, JAK2, p‐JAK2, STAT1, p‐STAT1, STAT3, and p‐STAT3 in hydrosalpinx group than those in control group with IL‐6 being mainly located in the cytoplasm and p‐JAK2, STAT1, p‐STAT1, STAT3, and p‐STAT3 in the cytoplasm and nucleus. JAK1 and p‐JAK1 was mainly located in the cytoplasm and JAK2 is in the cytoplasm and nucleus without difference of their expression between two groups. Consistently, hydrosalpinx group presented significantly higher protein levels of IL‐6, JAK1, p‐JAK1, JAK2, p‐JAK2, STAT1, p‐STAT1, STAT3, and p‐STAT3 than control group without difference of JAK1, p‐JAK1, JAK2 level.ConclusionThe activation of IL‐6/JAK2/STAT1 and STAT3 signaling pathways are found in the hydrosalpinx in infertile patients, indicating that they might be involved in the pathogenesis of hydrosalpinx.