Objective: To determine whether cervical dilation at the time of physical examination indicated cerclage placement can predicts latency and gestational age at delivery.
Methods: A retrospective cohort study of all women who underwent physical examination indicated cerclage placement from 1996 to 2011 at Duke University Hospital (DUH) was performed. Physical examination indicated cerclage was defined as cerclage placement after 16 weeks in women with a cervical length of less than 2.5 cm and/or cervical dilation greater than or equal to 1 cm at time of procedure. Subjects were divided into two groups depending on cervical dilation at time of procedure (2 cm, <2 cm) for comparison. A multivariate linear regression model for the outcome gestational age of delivery was constructed, controlling for confounding variables.
Results: A total of 110 women with complete data were available for analysis. Median gestational age at cerclage placement was similar between the two groups (20.3 vs. 20.3 weeks, p = 0.8). Women with cervical dilatation ≥ 2 cm dilation delivered at an earlier median gestational age than women with cervical dilation <2 cm (27.0 vs. 35.6 weeks, p < 0.001). Cervical dilation at the time of cerclage placement independently predicted gestational age at delivery while controlling for use of intracervical Foley balloon catheter for membrane reduction, cerclage suture type, history of prior preterm birth, race, insurance status, and tobacco use.
Conclusions: Women who receive a rescue cerclage are more likely to deliver at an earlier gestational age when cervical dilation is ≥ 2 cm at the time of procedure.