Cervical surveillance as an alternative to elective cervical cerclage for pregnancy management of suspected cervical incompetence

Abstract

The aim of the present study was to compare the outcome of pregnancies among patients with suspected cervical incompetence treated either by elective cervical cerclage or an alternative management program involving cervical surveillance. A prospective cohort study was performed in two groups of patients at risk of cervical incompetence with singleton gestations attending the Royal Women's Hospital, Melbourne, Australia, from 1996 to 2000. The first group was managed by their obstetric carers with an elective cerclage, while the second group was managed conservatively as part of a cervical surveillance program offered to patients attending the Department of Perinatal Medicine for pregnancy care. This program consists of weekly visits from 16 weeks' gestation and involves alternating transvaginal ultrasound assessment of cervical morphometry with cervico-vaginal bacteriology and fetal fibronectin swabs. Empiric insertion of a cerclage is undertaken when there is evidence of significant cervical shortening (cervical canal <2.5 cm in length at </=24 weeks). A total of 135 patients were identified for the study. Ninety-seven patients had an elective cervical cerclage inserted. Thirty-eight patients were followed through the cervical surveillance program. Twelve (32%) of the surveillance patients had a cerclage inserted at a mean gestational age of 20.6 weeks. There were no statistically significant differences between the groups in terms of maternal demographics or risk assessment scoring. One out of 38 (2.6%) patients of the surveillance group and 18/97 (18.6%) of the elective cerclage group delivered before 30 weeks' gestation (P = 0.034). Our study suggests that by only inserting a cerclage when indicated on the basis of ultrasound assessment of cervical morphometry, the number of cerclages required can be reduced while the perinatal outcome is significantly improved.