Does a cervical pessary reduce the incidence of preterm birth among pregnant women with a short cervix length and no history of preterm birth?

Among asymptomatic pregnant women with no history of preterm birth and a cervical length of less than 25 mm as identified by routine second-trimester ultrasound, the use of a cervical pessary resulted in a significant reduction in births at less than 34 weeks' gestation as compared with no pessary. Larger confirmatory trials are needed. (LOE = 1b-)

Saccone G, Maruotti GM, Giudicepietro A, Martinelli P; Italian Preterm Birth Prevention (IPP) Working Group. Effect of cervical pessary on spontaneous preterm birth in women with singleton pregnancies and short cervical length: A randomized clinical trial. JAMA 2017;318(23):2317-2324.  [PMID:29260226]

Randomized controlled trial (nonblinded)

Unknown/not stated

Concealed

Outpatient (specialty)

This randomized clinical trial investigated the use of a cervical pessary for the prevention of preterm birth among women found to have a cervix length of 25 mm or less (N = 300) at the time of routine second-trimester obstetrical ultrasound. The trial was conducted at a single center in Italy. Scans were performed at between 18 weeks 0 days and 23 weeks 6 days gestational age. Women were included if they had an asymptomatic singleton pregnancy and no prior history of preterm birth. Women were excluded at the time of randomization if they had multiple gestation, ruptured membranes, lethal fetal structural abnormality, cerclage, vaginal bleeding, suspicion of chorioamnionitis, placenta previa or placenta accreta, ballooning of membranes outside the cervix, or painful regular uterine contractions. Women were randomized to receive either cervical pessary (n = 150) or no pessary (n = 150). Randomization was stratified by cervical length: 20 mm or shorter, or longer than 20 mm (up to 25 mm). Although the study was not masked for women or their healthcare providers, allocation was concealed and outcome assessment was masked. The Arabin cervical pessary was put in place at randomization and left in place until 37 weeks' gestation, or taken out earlier if clinically indicated. Women in both groups with cervical length of 20 mm or less also used intravaginal progesterone 200 mg suppositories daily. The principal outcome of preterm birth at less than 34 weeks' gestation was significantly reduced in the pessary group: 11/150 (7.3%) vs 23/150 (15.3%); P = .04; number needed to treat = 13; 95% CI 7 - 130. There were more cases of vaginal discharge in the pessary group, but no significant differences in pelvic discomfort or chorioamnionitis. The study was relatively small to study secondary outcomes and adverse events.