(1066) Characteristics associated with previable delivery and/or delivery <21 days after transvaginal cervical cerclage placement

To identify socio-demographic, clinical and sonographic predictors of cerclage failure, defined as previable delivery or delivery < 21 days after transvaginal cervical cerclage placement, among women with singleton gestations.

Study Design:

We conducted a retrospective cohort study of women undergoing a transvaginal cervical cerclage at a single tertiary academic center between 2008 to 2020. Data pertaining to maternal demographics, obstetric course, sonographic cervical length, and cerclage operative technique were abstracted and compared across groups with and without cerclage failure. Covariates with P≤0.2 on univariate analyses were considered for incorporation into a logistic regression model for prediction of cerclage failure.

Results:

Out of 1086 cases, a total of 754 women with singleton gestations were included in the analyses. 66 (9%) pregnancies had a previable delivery and/or delivered < 21 days after cerclage placement. Post-operative cervical length ≤20 mm at ≤24 weeks, ≥1 cm dilation prior to cerclage placement, and concomitant vaginal progesterone use were independently associated with cerclage failure. Prior spontaneous preterm birth >16 weeks, history of prior delivery ≥34 weeks, and nulliparity were not significantly associated with the outcome. The bias-corrected bootstrapped (1000 repetitions) AUROC for the model predictive of cerclage failure was 0.83 (95% CI 0.74-0.87). Placental pathology revealed 48 (76%) of cases had evidence of moderate-to-severe chorioamnionitis (stage II-III maternal inflammatory response) and 30 (48%) had evidence of funisitis.

Conclusion:

Our research found that concomitant vaginal progesterone use was associated with decreased risk of cerclage failure, while pregnancies with preoperative cervical dilation ≥1 cm and/or a postoperative cervical length ≤20 mm documented at ≤24 weeks warrant close surveillance due to increased risk of cerclage failure. Our research offers critical insight into identification of the highest risk cohort likely to experience adverse perinatal outcomes in the context of cerclage failure.