Interleukin‐8 is involved in cervical dilatation but not in prelabour cervical ripening

SUMMARY Our aim was to determine the amount and source of interleukin (IL)‐8 and to study IL‐8 receptor expression in the human cervix during pregnancy and after labour. Cervical biopsies were obtained from six non‐pregnant women, eight women undergoing pregnancy termination, 17 women undergoing elective caesarean section and 11 women after vaginal delivery. IL‐8 levels were compared in women with and without a ripe cervix, as determined by cervical Bishop score and cervicovaginal fetal fibronectin levels. Levels of IL‐8 and IL‐1β, a regulator of IL‐8 expression, were determined by enzyme‐linked immunosorbent assay (ELISA). IL‐8, IL‐1β and IL‐8 receptor proteins were localized by immunohistochemistry. Compared with late pregnancy, IL‐8 levels increased after labour and vaginal delivery (P