Objective: To investigate the outcomes of singleton pregnant women with cervical insufficiency undergoing two different cervical cerclages.
Methods: This is a retrospective cohort study of women who underwent a history- or ultrasound-indicated cerclage (either Shirodkar or McDonald) at a tertiary referral center from 2002 to 2014. Outcome parameters (delivery age, postoperative cervical length, preterm premature rupture of membranes, preterm delivery rate and neonatal complications) were compared between the two cerclage procedures. Multivariate logistic regression analysis was applied to control for significant variables of preterm birth. Kaplan-Meier survival analysis was used to demonstrate delivery age to percentage of term delivery by cerclage type.
Results: Ninety-four cases were initially included. After excluding cases not meeting the study criteria, 60 pregnancies (Shirodkar 36 and McDonald 24) were recruited for analysis. The mean delivery age in the Shirodkar group was more advanced than that in the McDonald group (37.1 ± 3.3 versus 34.8 ± 4.9 weeks, p = 0.039). There were significantly fewer deliveries <37 gestational weeks in the Shirodkar group than in the McDonald group (30.6% versus 58.3%, p = 0.033) but no significant differences in deliveries <28, 32 and 34 gestational weeks. No significant differences were found in neonatal complications except for respiratory distress syndrome (5.6% in Shirodkar versus 29.2% in McDonald, p = 0.023).
Conclusion: In the setting of history-indicated or ultrasound-indicated cerclage, Shirodkar was superior to McDonald in the prevention of late preterm birth and neonatal respiratory distress syndrome.
Keywords: Cerclage; McDonald; Shirodkar; cervical insufficiency; late preterm birth; respiratory distress syndrome.