Cerclage is one of the interventions to prevent spontaneous preterm birth (sPTB). This study aimed to identify predictive factors of cerclage success in preventing sPTB.METHODS:
Retrospective study of singleton pregnancy at high risk of sPTB in University of Illinois at Chicago between 2013 and 2017. Baseline characteristics, duration of pregnancy, pregnancy outcomes and other predictive factors were analyzed using χ2, student t test, and multiple logistic regression analysis.RESULTS:
Of the 310 women identified, 90 (29%) had rescue cerclage, and 65 (21%) had prophylactic cerclage. Most statistically significant predictors of sPTB of rescue cerclage were insertions at 17–20 weeks, aOR 2.26 (95% CI: 1.47–3.50, P<.0001), and at 21–22 weeks, aOR 1.81 (95% CI: 1.15–2.87, P<.0001). Cerclages placed at CL <10 mm was associated with increased likelihood of sPTB, aOR 1.60 (95% CI: 1.10–2.34, P<.0001). Cervical length at 21–25 mm and cerclage at GA <16 weeks were associated with decreased rate of sPTB, aOR 0.40 (95% CI: 0.26–0.61, P<.0001), and aOR 0.26 (95% CI: 0.16–0.40, P<.0001). Except for indomethacin in prophylactic cerclage, cervical dilatation, funneling, presence of sludge, prior sPTB, vaginal infections and use of 17-OHPC, these were not statistically significant in preventing sPTB.CONCLUSION:
The success of cerclage in the prevention of sPTB depends on several factors. The most predictive factors were the degree of short cervix and earlier GA at cerclage placement.