The outcome of cervical resistance index study and cervical cerclage in a tertiary referral centre - a retrospective cohort study

Abstract

This retrospective cohort study reviews the patients who underwent cervical resistance index (CRI) study and cervical cerclage in a tertiary referral centre. The authors included patients in a period of 5 years, with 42 cerclages and 30 CRIs. The elective cervical cerclages were inserted in the late first or early second trimester of pregnancies. A few emergency rescue cerclages were inserted after 24 weeks. 89% of patients with elective cerclages delivered beyond 33 weeks gestation. 58% of rescue cerclages delivered after 32 weeks gestation. 2 patients had rescue cerclages, after the initial elective cerclages in the same pregnancies. CRI produced variable results from 0 to more than 40. The group of CRI result 15 to 19 had the most patients. CRIs up to 22 were offered cerclages. There were inconsistencies in the recommendation for equivocal CRIs from 22 to 29. All CRIs beyond 29 had subsequent term pregnancies without cervical cerclage. Patients who had term pregnancies, and subsequently spontaneous abortions or preterm deliveries can be diagnosed with cervical incompetence from CRIs. In conclusion, majority of patients had pregnancies beyond 32 weeks with cervical cerclages. CRI can be a useful tool to diagnose cervical incompetence and for recommending cervical cerclages in subsequent pregnancies.