Combined treatment of McDonald cerclage and Arabin-pessary: a chance in the prevention of spontaneous preterm birth?

Background: Patients with cervical shortening obtained by transvaginal ultrasound and/or previous preterm delivery are at increased risk for preterm birth in the current pregnancy. The aim of the present cohort study was to compare the rate of preterm birth and early neonatal parameters in patients at risk and screening patients who received either a cerclage or a combined treatment of cerclage and cervical pessary.Methods: A retrospective cohort study was conducted from March 2005 to March 2017 including all patients in our department which received a McDonald cerclage or a combined treatment of McDonald cerclage and an Arabin pessary. A total of 81 women with singleton pregnancies were considered the final sample of this cohort study, of whom 34 patients received a cerclage and 47 patients received a cerclage combined with a pessary. Patients "at risk" with a history of preterm birth at <37 weeks of gestation, late-term abortion, conization, or cervical cerclage in a previous pregnancy because of a cervical shortening <10th percentile and women with no inherent historic risk factors but a current cervical length <3rd percentile (screening group) were analyzed separately. We defined delivery <34 weeks of gestation as the primary outcome. Secondary outcomes were preterm birth (PTB) <28, <32, and <37 weeks of gestation, admission to the neonatal intensive care unit (NICU), neonatal admission time, birthweight, and prolongation of the gestation.Results: There were no differences between the two study groups with regard to baseline characteristics. Delivery <34 weeks of gestation occurred in 32.4 and 27.7% of patients treated with cerclage versus combined treatment respectively (p = .48). Similarly, there was no difference in the rate of preterm birth at <28, <32, or <37 weeks of gestation. The mean neonatal admission time at the neonatal intensive care unit was shorter in the combined treatment group versus in the cerclage group (p = .02). There was a trend for higher birthweight (2368 g ± 962 vs. 2650 g ± 1063) in favor of the combined treatment arm (p = .077).Conclusion: The combined treatment of cerclage with an Arabin pessary seems to be a considerable alternative in the prevention of spontaneous PTB (sPTB), especially for patients with cervical length <3rd percentile, and in particular for patients with amnion prolapse in terms of birthweight and neonatal admission time.