Predictors of Outcomes of Non-Elective Cervical Cerclages

Background: Non-elective cervical cerclages are associated with significant perinatal complications. There is scant available information about what the predictors of these outcomes are, thus making counselling difficult.

Objective: To identify which factors predict delivery at or beyond 28, 34, and 37 weeks' gestation in women with emergency/rescue cervical cerclage.

Methods: We conducted a retrospective cohort study of nonelective cerclages over 10 years in our centre. We included women with singleton pregnancies, morphologically normal fetuses, and a cervix dilated to at least 1 cm. Our primary outcome was delivery at or beyond 28 weeks' gestation, and secondary outcomes consisted of delivery at or beyond 34 and 37 weeks' gestation. Descriptive statistical and logistic regression analyses were performed.

Results: We identified a total of 69 cases, and 47 met the inclusion criteria; 44.6% of these women delivered at or beyond 28 weeks' gestation. Membranes seen in the vagina on ultrasound and postcerclage preterm premature rupture of membranes decreased the chance of delivery at or beyond 28 weeks by 81.7% (OR 0.183; 95% CI 0.048 to 0.703) and 95% (OR 0.050; 95% CI 0.006 to 0.429), respectively. The same factors were predictive of deliveries at or beyond 34 and 37 weeks' gestation.

Conclusion: Membranes seen in the vagina on ultrasound and postcerclage pre-labour premature rupture of membranes were the strongest predictors of failure to reach 28 weeks' gestation. This information is of critical importance when counselling patients about non-elective cervical cerclage.