Cervical Pessary Compared With Vaginal Progesterone for Preventing Early Preterm Birth

Abstract

OBJECTIVE: To compare the effectiveness of a cervical pessary and vaginal progesterone to prevent spontaneous preterm births in pregnant women with cervical lengths 25 mm or less as measured by transvaginal ultrasonography. METHODS: This was a multicenter, open-label, randomized, noninferiority trial. Women with singleton pregnancies and a short cervix (25 mm or less) measured transvaginally at the second-trimester ultrasonogram were invited to participate. They were computer-randomized (one to one) into cervical pessary placement or treatment with vaginal progesterone (200 mg/24 hours). The primary outcome was spontaneous preterm delivery before 34 weeks of gestation. The noninferiority margin was set at 4% with a 0.025 one-sided α level and a statistical power of 80%. That is, if the 95% CI upper bound exceeded 4%, the pessary could not be deemed noninferior. A sample size of 254 women was required to show noninferiority of the pessary to progesterone. RESULTS: The trial was conducted from August 2012 to April 2016 with the participation of 27 Spanish hospitals. A total of 254 patients were enrolled and 246 included in the intention-to-treat analysis. Demographic and baseline characteristics were similar across groups. The rate of spontaneous delivery before 34 weeks of gestation was 14% (n=18/127) in the pessary group and 14% (n=17/119) in the progesterone group with a risk difference of −0.11% (95% CI −8.85% to 8.62%; P=.99), that is, noninferiority was not shown for the pessary. The incidence of increased vaginal discharge (87% vs 71%, P=.002) and discomfort (27% vs 3%, P<.001) was significantly higher in the pessary group. CONCLUSION: A cervical pessary was not noninferior to vaginal progesterone for preventing spontaneous birth before 34 weeks of gestation in pregnant women with short cervixes. CLINICAL TRIAL REGISTRATION: EU Clinical Trials Register, 2012-000241-13; ClinicalTrials.gov, NCT01643980.

Cervical pessary to prevent preterm birth in asymptomatic high-risk women: a systematic review and meta-analysis

“…Selection, characteristics, and risk of bias of studies Figure 1 summarizes the process of identification and selection of studies. Twelve studies, 160e171 which included 4687 women and 7167 fetuses/infants, met the inclusion criteria: 8 evaluated pessary vs no pessary in women with a short cervix (6 in singleton gestations 160e165 and 2 in twin gestations 169,170 ), 2 assessed pessary vs no pessary in unselected multiple gestations (1 in twin gestations 168 and another in both twin and triplet gestations 167 ), and 2 compared pessary vs vaginal progesterone in women with a short cervix (1 in singleton gestations 166 and another in twin gestations 171 ). The study by Liem et al 167 did not report outcome data separately for twin and triplet gestations.…”

Reducing the Risk of Preterm Birth by Ambulatory Risk Factor Management

“…Women with singleton pregnancies were included, who had sonographically confirmed cervical (16). In case of a cervical length ≤ 25 mm before 24 weeks' gestation, a recently published RCT showed non-inferiority for placing a cervical pessary compared with vaginal administration of progesterone before 34 weeks' gestation (14% versus 14%; risk difference: 0.11%; [-8.85; -8.62]) (17). Additional application of vaginal progesterone did not reduce the preterm birth rate before 34 and 37 weeks' gestation compared with the pessary alone (18).…”

Cervical Pessary Plus Progesterone for Twin Pregnancy with Short Cervix Compared to Unselected and Non-Treated Twin Pregnancy: A Historical Equivalence Cohort Study (EPM Twin Pessary Study)

“…4 One strength of the present study could be the change in the rates of PB using a mechanical device, which has been demonstrated as secure, and with a low rate of fetal and maternal complications; due to the presence of the device, the patients described that they felt safer regarding the attachment to the cervix itself, and these data had not yet been described on the literature. 32 Another strength of the methods herein employed was the application of transvaginal ultrasound after the insertion of the pessary. It was only because of the ultrasound that we were able to recognize patients with the pessary in a bad position; after the diagnosis, the device was repositioned in all of those cases.…”