Primary, secondary, and tertiary preventions of preterm birth with cervical cerclage.

ABSTRACT

OBJECTIVE: To evaluate the efficacy of cerclage in preventing preterm birth according to indication. STUDY DESIGN: Retrospective analysis of all women who underwent cerclage to prevent preterm birth in a university-affiliated medical-center (2007-2017). Multiple gestations were excluded. Cohort was divided to three subgroups according to cerclage indication group A-primary prevention cerclage, performed during the first trimester, based on a history of cervical insufficiency; group B-secondary prevention cerclage, performed after sonographic visualization of asymptomatic cervical length shortening and previous preterm birth; and group C-tertiary prevention cerclage, performed at mid-trimester in women presenting with asymptomatic cervical dilatation. Primary outcome was gestational age at delivery. Secondary outcomes were maternal and neonatal complications. RESULTS: During the study period 273 women underwent cervical cerclage group A-215 (79%), group B-25 (9%), and group C-33 (12%). Patients in group C had significantly lower gravidity and parity. Gestational age at cerclage was highest in group C and lowest in group A (22 vs. 13 weeks p < 0.001). Median gestational age at delivery was 37 + 3 weeks in groups A and B and 34 + 3 in group C. This difference persisted after controlling for potential confounders (p < 0.0001). Preterm birth prior to 34 weeks of gestation were 10.7% in group A, 16% in group B, and 33.33% in group C (p = 0.0021). Neonatal complications including respiratory distress syndrome, intraventricular hemorrhage, and necrotizing enterocolitis, were clmore prevalent in group C. CONCLUSION: Cerclage was shown to be an acceptable measure in cases of an anticipated increased risk of preterm birth with a low rate of procedure associated complications. However, the number-needed-to-treat cannot be determined from our data, because a control group was lacking.