Table 2: Randomized controlled trials.

AuthorYearCountryNo. of womenInclusion criteriaExclusion criteriaAgeType of pessaryPregnancy outcomeNeonatal outcomePessary removal Side effects of pessary

Forster1986Germany242Not clearly statedNot clearly stated Mean age pessary:
26.6 sd 6.13
Mean age cerclage:
26.3 sd 4.22
StützpessaryPessary versus control mean GA at delivery: 35.15–37.57 weeksPessary versus control birthweight:
3097.9 versus 3062.7 g
Neonatal mortality:
0 (0%) versus 1 (0.89%)
Not statedNot stated

Gmoser1991Germany300 Women with cervical changes (with or without contractions), history of cervical incompetence, twin pregnancies or a previous pregnancy with a cerclageNot clearly statedNot clearly statedStutzpessaryPessary versus control median GA at delivery:
39–36 weeks
Pessary versus control birthweight:
2950–2400 gram
Not statedNot stated

Goya2012Spain385Singleton pregnancies CL <25 mm at 18–22 weeks Major fetal abnormalities
Regular uterine contractions
Active vaginal bleeding
Ruptured membranes placenta praevia
History of cone biopsy cervical Cerclage in situ
18–43 yearsArabin Pessary versus control
delivery <28 weeks:
4 (2%)–16 (8%)
delivery <34 weeks:
12 (6%)–53 (28%)
delivery <37 weeks:
41 (22%)–113 (59%)
mean GA at delivery:
37.7–34.9 weeks
Pessary versus control
composite adverse outcome:
5 (3%)–30 (16%)
birthweight < 1500 g:
9 (5%)–26 (14%)
birthweight < 2500 g:
17 (9%)–56 (29%)
37 weeks of gestation
Risk of PTB with persistent
Contractions despite tocolysis
Vaginal bleeding
Patient discomfort
All women had increased vaginal discharge

Hui2012China108Singleton pregnancies
CL <25 mm at 18–22 weeks
Major fetal abnormalities
Regular uterine contractions
History cervical incompetence
Ruptured membranes
multiple gestation
Cervical dilatation
Cervical cerclage:
current or previous pregnancy
22–44 yearsArabinPessary versus control
delivery <28 weeks:
2 (3.8%)–3 (5.5%)
delivery <34 weeks:
5 (9.4%)–3 (5.5%)
delivery <37 weeks:
8 (15.1%)–10 (18.2%)
mean GA at delivery:
38.1–37.8 weeks
Pessary versus control
Clinical sepsis:
3 (5.7%)–5 (9.4%)
Jaundice:
15 (28.3%)–14 (26.4%)
RDS:
5 (9.4%)–2 (3.8%)
IVH:
0 (0%)–1 (1.9%)
NICU admission:
21 (39.6%)–17 (32.1%)
37 weeks of gestation
Ruptured membranes
Vaginal bleeding
Painful contractions
25 (47%) increased discharge
4 (8%) pressure sensations
2 (4%) dislodge pessary
1 (2%) vaginal bleeding
1 (2%) pain
1 (2%) urine retention