This review summarizes evidence supporting history-indicated cerclage and the evolution of commonly used eligibility thresholds. Randomized trials and meta-analyses demonstrate that cerclage reduces very early preterm birth in high-risk pregnancies without meaningful heterogeneity of treatment effect across risk strata. Although studies comparing cervical length surveillance versus history-indicated cerclage report similar population-level outcomes, differences in patient selection and study design limit interpretation. History-indicated cerclage, therefore, remains an important option for selected patients at risk for pregnancy loss or extreme preterm birth. Current evidence highlights the importance of individualized counseling and shared decision-making that incorporates clinical history, risk assessment, and patient preferences.
Young et al. (Fri,) studied this question.