Endocervical immune mediator production following successful rescue or ultrasound indicated cerclage placement.

OBJECTIVE

Placement of a cervical cerclage at mid-trimester in women at risk for preterm labor is a common procedure with apparent benefits for some women. However, the changes that occur in the cervix following this procedure remain incompletely identified.

METHODS

We evaluated the endocervical concentrations of mediators involved in extracellular matrix (ECM) stabilization or degradation prior to, and up to 120 days following, cerclage placement in 53 women who underwent an ultrasound-indicated or a rescue cerclage at 15-25 weeks of gestation due to a cervical length <1.5 cm. All delivered a healthy neonate at term. Samples were tested by enzyme-linked immunosorbent assay for concentrations of hyaluronan (HA), 27 kDa heat shock protein (hsp27), transforming growth factor-β (TGF-β), extracellular matrix metalloproteinase inducer (CD147/EMMPRIN), and matrix metalloproteinase (MMP)-1 and -8.

RESULTS

Concentrations of both HA and hsp27 were highest at the time of cerclage placement and then decreased while TGF-β and EMMPRIN increased in concentration following the procedure. The highest mean EMMPRIN level was measured at >90 days following the procedure while TGF-β levels peaked at 61-90 days post-cerclage. MMP-1 and MMP-8 were not detected over the study time period.

CONCLUSION

In women with a successful cerclage placement the selective regulation of mediators inhibits progression of ECM degradation and cervical ripening.