Term Labor Outcomes after Cerclage Placement in a Multi-institutional Cohort

The placement of a cervical cerclage in early pregnancy could influence subsequent labor outcomes at term. Prior studies have yielded conflicting results regarding the potential association with adverse labor outcomes such as cesarean delivery (CD), cervical laceration, and prolonged labor. Our objective was to evaluate rate of CD and adverse maternal outcomes in women who labored at term with and without a cerclage within the Consortium on Safe Labor (CSL) cohort. We hypothesize that women with a cerclage in the incident pregnancy will have an increased frequency of CD and other adverse term labor outcomes.

A retrospective cohort study was performed using data from the CSL. Women with live nonanomalous singleton gestations≥ 37 weeks with induced or spontaneous labor were identified. The risk of CD and other maternal and neonatal outcomes were compared between women with and without cerclage placement during pregnancy. Univariable and multivariable analyses were performed with adjustment for confounding factors. Planned subgroup analysis by history of CD was performed.

A total of 374 of the 147,463 patients who met study inclusion criteria in the CSL (0.25%) had a cerclage. In univariable analysis, cerclage placement was associated with a significant increase in the frequency of CD (17.1 vs. 12.8%, p = 0.016, odds ratio: 1.4, 95% CI: 1.07-1.84), cervical lacerations, infectious morbidity, and blood loss. The association with CD persisted in multivariable regression. Cerclage placement was not associated with an increased risk of neonatal morbidity.

Cerclage placement in pregnancy is associated with an increased risk of CD, cervical laceration, and infectious morbidity among women delivering at term. These findings suggest that cerclage placement may impact labor progression and outcomes. However, the magnitude of the association may not alter clinical decisions regarding cerclage placement in appropriate candidates.