Normal and premature rupture of fetal membranes at term delivery differ in regional chemotactic activity and related chemokine/cytokine production.

A gradient of immunological mediators exists in the fetal membranes from the periplacental zone (PZ) to the rupture zone (RZ) at term delivery (rupture of fetal membranes [ROM]). However, it is unknown if this gradient is different in premature rupture of these tissues (premature rupture of fetal membranes [PROM]). We therefore analyzed leukocyte chemotactic activity and chemokine/cytokine production in fetal membrane zones in ROM and PROM. In ROM, leukocyte chemotactic activity increased from the PZ to the RZ; however, this did not occur in PROM. This was due to consistently elevated leukocyte chemotactic activity in PROM compared to ROM tissues. In the RZ, ROM was characterized by increased T-cell attraction and high levels of chemokine (C-X-C motif) ligand 8 (CXCL-8)/interleukin 8, and PROM by increased granulocyte attraction and high levels of granulocyte-macrophage colony-stimulating factor and CXCL-10/interferon gamma-induced protein 10. We conclude that normal and premature rupture of fetal membranes differ in regional chemotactic activity and related chemokine/cytokine production, which may represent evidence for differential mechanisms of rupture at term delivery.