Can a cervical pessary help prevent preterm birth?
Research to date on use of a silicone pessary around the cervix to prevent preterm birth has produced contradictory results. Adding to those data are outcomes from a new randomized controlled trial, which cast doubt on the value of the devices.
Published in The New England Journal of Medicine, the findings are from a multicenter comparison of pessary placement and expectant management by researchers from UK. The participants were 930 women aged ≥16 with singleton pregnancies and cervical lengths ≤25 mm at 20 weeks 0 days to 24 weeks 6 days gestation.
Half the participants received cervical pessaries and half were followed expectantly. Vaginal progesterone was administered to 423 woman with a cervical length ≤15 mm at randomization or on a subsequent visit. Antibiotics were administered to 267 of the women who had positive vaginal cultures and cervical cerclages were placed in 7 women with very short cervixes.
The primary outcome of the study was spontaneous delivery before 34 weeks’ gestation, which occurred in 55 (12.0%) of the women who had pessaries and 50 (10.8%) of the women in the control group (odds ratio in the pessary group 1.12; 95% confidence interval [CI] 0.75 to 1.69; P=0.57). No significant difference was seen between the pessary and expectant management groups in percentage of women who did not give birth spontaneously before 34 weeks (hazard ratio in the pessary group 1.13; 95% CI 0.77 to 1.65; P=0.54). Adjustment for cervical length, progesterone use, and antibiotic treatment did not change the results.
Looking at adverse events, the investigators found that pessary placement did not affect rates of perinatal death, adverse neonatal outcomes, or need for neonatal special care. The women who received the devices did have more vaginal discharge than those in the control group (10.5% vs. 6.2%; P=0.02).