How does physical readiness manifest in patients who need cerclage?

The need for a cerclage is often indicated by the presence of specific cervical dilatation or effacement without active labor. In this context, a dilation of 1-4 cm at the internal os suggests a significant risk for preterm birth, which is the main indication for the placement of a cervical cerclage. The purpose of a cerclage is to provide mechanical support to the cervix, helping to prevent premature delivery due to cervical insufficiency.

Options discussing a history of previous preterm birth or cervical incompetence may reflect broader risk factors but do not directly manifest as physical readiness for cerclage as the situation of existing cervical dilation does. Additionally, the presence of signs of labor complicates the candidacy for cerclage, as the procedure is generally avoided in those actively in labor. Therefore, the physical manifestation of 1-4 cm dilation at the internal os aligns with the rationale for deploying a cerclage to prevent further progression of cervical changes leading to preterm labor.