BACKGROUND: Preterm birth (PTB), defined as birth prior to 37 weeks of gestation, occurs in ten percent of all pregnancies. PTB is responsible for more than half of neonatal and infant mortalities and morbidities. Because cervical insufficiency is a common cause of PTB, one possible preventive strategy involves insertion of a cervical pessary to support the cervix. Several published studies have compared the use of pessary with different management options and obtained questionable results. This highlights the need for an up-to-date systematic review of the evidence.
OBJECTIVES: To evaluate the benefits and harms of cervical pessary for preventing preterm birth in women with singleton pregnancies and risk factors for cervical insufficiency compared to no treatment, vaginal progesterone, cervical cerclage or bedrest.
SEARCH METHODS: We searched Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform to 22 September 2021. We also searched the reference lists of included studies for additional records.
SELECTION CRITERIA: We included published and unpublished randomised controlled trials (RCTs) comparing cervical pessary with no treatment, vaginal progesterone, cervical cerclage or bedrest for preventing PTB. We excluded quasi-randomised trials. Our primary outcome was delivery before 34 weeks' gestation. Our secondary outcomes were 1. delivery before 37 weeks' gestation, 2. maternal mortality, 3. maternal infection or inflammation, 4. preterm prelabour rupture of membranes, 5. harm to woman from the intervention, 6. maternal medications, 7. discontinuation of the intervention, 8. maternal satisfaction, 9. neonatal/paediatric care unit admission, 10. fetal/infant mortality, 11. neonatal sepsis, 12. gestational age at birth, 13. harm to offspring from the intervention 14. birthweight, 15. early neurodevelopmental morbidity, 15. late neurodevelopmental morbidity, 16. gastrointestinal morbidity and 17. respiratory morbidity.
DATA COLLECTION AND ANALYSIS: Two review authors independently assessed trials for eligibility and risk of bias, evaluated trustworthiness based on criteria developed by the Cochrane Pregnancy and Childbirth Review Group, extracted data, checked for accuracy and assessed certainty of evidence using the GRADE approach.
MAIN RESULTS: We included eight RCTs (2983 participants). We included five RCTs (1830 women) in the comparison cervical pessary versus no treatment, three RCTs (1126 pregnant women) in the comparison cervical pessary versus vaginal progesterone, and one study (13 participants) in the comparison cervical pessary versus cervical cerclage. Overall, the certainty of evidence was low to moderate due to inconsistency (statistical heterogeneity), imprecision (few events and wide 95% confidence intervals (CIs) consistent with possible benefit and harm), and risk of performance and detection bias. Cervical pessary versus no treatment Cervical pessary compared with no treatment may reduce the risk of delivery before 34 weeks (risk ratio (RR) 0.72, 95% CI 0.33 to 1.55; 5 studies, 1830 women; low-certainty evidence) or before 37 weeks (RR 0.68, 95% CI 0.44 to 1.05; 5 studies, 1830 women; low-certainty evidence). However, these results should be viewed with caution because the 95% CIs cross the line of no effect. Cervical pessary compared with no treatment probably has little or no effect on the risk of maternal infection or inflammation (RR 1.04, 95% CI 0.87 to 1.26; 2 studies, 1032 women; moderate-certainty evidence). It is unclear if cervical pessary compared with no treatment has an effect on neonatal/paediatric care unit admission (RR 0.96, 95% CI 0.58 to 1.59; 3 studies, 1332 infants; low-certainty evidence) or fetal/neonatal mortality (RR 0.93, 95% CI 0.58 to 1.48; 5 studies, 1830 infants; low-certainty evidence) because the 95% CIs are compatible with a wide range of effects that encompass both appreciable benefit and harm. Cervical pessary versus vaginal progesterone Cervical pessary may reduce the risk of delivery before 34 weeks (RR 0.72, 95% CI 0.52 to 1.02; 3 studies, 1126 women; moderate-certainty evidence) or before 37 weeks (RR 0.89, 95% CI 0.73 to 1.09; 3 studies, 1126 women; moderate-certainty evidence), but we are uncertain of the results because the 95% CI crosses the line of no effect. The intervention probably has little or no effect on maternal infection or inflammation (RR 0.95, 95% CI 0.81 to 1.12; 2 studies, 265 women; moderate-certainty evidence). It is unclear if cervical pessary compared with vaginal progesterone has an effect on the risk of neonatal/paediatric care unit admission (RR 0.98, 95% CI 0.49 to 1.98; low-certainty evidence) or fetal/neonatal mortality (RR 1.97, 95% CI 0.50 to 7.70; 2 studies; 265 infants; low-certainty evidence) because the 95% CIs are compatible with a wide range of effects that encompass both appreciable benefit and harm. Cervical pessary versus cervical cerclage Only one very small study of 13 pregnant women contributed data to this comparison; the results were unclear.
AUTHORS' CONCLUSIONS: In women with a singleton pregnancy, cervical pessary compared with no treatment or vaginal progesterone may reduce the risk of delivery before 34 weeks or 37 weeks, although these results should be viewed with caution due to uncertainty around the effect estimates. There is insufficient evidence with regard to the effect of cervical pessary compared with cervical cerclage on PTB. Due to low certainty-evidence in many of the prespecified outcomes and non-reporting of several other outcomes of interest for this review, there is a need for further robust RCTs that use standardised terminology for maternal and offspring outcomes. Future trials should take place in a range of settings to improve generalisability of the evidence. Further research should concentrate on comparisons of cervical pessary versus cervical cerclage and bed rest. Investigation of different phenotypes of PTB may be relevant.
INTRODUÇÃO: Redução de parto prematuro é um importante objetivo na assistência obstétrica. Foi realizada uma revisão sistemática de ensaios clínicos randomizados e estudos de coorte sobre a eficácia do pessário cervical para impedir o nascimento prematuro. MÉTODO: Foram pesquisados os bancos de dados eletrônicos do Medline e Embase, desde o início até abril de 2012 para identificar estudos que investigam o tratamento com um pessário cervical para impedir o nascimento prematuro. Construímos dois-por-dois quadros para entrega antes de 28, 34 e 37 semanas de gestação e riscos relativos calculados (RR) com intervalo de confiança de 95%. RESULTADOS: A pesquisa encontrou 103 resumos potencialmente elegíveis, dos quais seis estudos de coorte e quatro ensaios clínicos randomizados (ECR) investigaram a eficácia do pessário. Um ECR (n = 380), demonstraram uma taxa de libertação inferior antes de 34 semanas (RR de 0,24, IC de 95% 0,13-0,43) no grupo pessário, enquanto outro ECR (n = 108) não mostrou qualquer efeito positivo para a entrega do pessário antes 34 semanas (RR 1,73, IC de 95% 0,43-6,88). Dois estudos randomizados quase mais velhos e estudos de coorte indicou potencial efeito do pessário. CONCLUSÕES: Disponíveis estudos randomizados e não randomizados indicam potencial eficácia de um pessário cervical na prevenção do parto prematuro. São necessários ensaios clínicos randomizados antes de mais este dispositivo pode ser utilizado na prática clínica.
FUNDAMENTO: O parto prematuro é um problema de saúde importante e contribui para mais de 50% da mortalidade geral. O nascimento prematuro tem múltiplos factores de risco, incluindo a incompetência cervical e gravidez múltipla. Estratégias de gestão de diferentes foram tentou impedir o nascimento prematuro, incluindo a cerclagem cervical. Cerclagem cervical é um método invasivo e que necessita de anestesia pode estar associada a complicações. Além disso, ainda há controvérsias sobre a eficácia e o grupo de pacientes que poderiam se beneficiar com esta operação. Cervical pessário foi tentado como uma alternativa simples, não-invasivo, que pode substituir a operação ponto cervical invasivo acima para impedir o nascimento prematuro.
OBJETIVOS: Avaliar a eficácia do pessário cervical para a prevenção do parto prematuro em mulheres com fatores de risco para a incompetência cervical.
Métodos de busca: Pesquisamos o Cochrane Gravidez e do Grupo Parto Trials Register (1 de Setembro de 2012), Controlled Trials atual eo New Zealand Clinical Trials Registry australiano (1 de Setembro de 2012).
CRITÉRIOS DE SELEÇÃO: Foram selecionados todos publicados e ensaios clínicos randomizados não publicados comparando o uso de pessário cervical com a gestão cerclagem cervical ou expectante para a prevenção do parto prematuro. Nós não incluem ensaios quasi-randomizados. Ensaios Cluster-randomizados ou cross-over não eram elegíveis para inclusão.
COLETA DE DADOS E ANÁLISE: Dois revisores avaliaram independentemente os ensaios para a inclusão.
PRINCIPAIS RESULTADOS: A revisão incluiu um estudo randomizado controlado. O estudo incluiu 385 mulheres grávidas com colo curto de 25 mm ou menos que estavam entre 18 a 22 semanas de gravidez. O uso de pessário cervical (192 mulheres) foi associado com uma diminuição estatisticamente significativa na incidência de parto prematuro espontâneo gestação inferior a 37 semanas, em comparação com a conduta expectante (22% versus 59%, respectivamente, taxa de risco (RR) 0,36, 95 % de intervalo de confiança (IC) de 0,27-0,49). Espontâneo parto prematuro antes de 34 semanas, foi estatisticamente significativamente reduzida no grupo pessário (6% e 27%, respectivamente, RR 0,24, IC 0,13-0,43 95%). A média de idade gestacional no parto foi de 37,7 + 2 semanas no grupo pessário e 34,9 + 4 semanas no grupo expectante. As mulheres do grupo pessário usado menos tocolítico (RR 0,63, IC ,50-,81 95%) e corticosteróides (RR 0,66, IC 0,54-0,81 95%) do que o grupo expectante. Corrimento vaginal foi mais comum no grupo pessário (RR 2,18, IC 1,87-2,54 95%). Entre o grupo pessário, 27 mulheres precisavam reposicionamento pessário sem remoção e houve um caso de remoção do pessário. Noventa e cinco por cento das mulheres no grupo pessário recomendaria esta intervenção de outras pessoas. Neonatal admissão cuidados pediátricos foi reduzida no grupo de pessário em comparação com o grupo de expectativa (RR de 0,17, IC 0,07-0,42 95%).
Conclusão dos autores: A revisão incluiu apenas um bem concebido ensaio clínico randomizado que mostrou efeito benéfico do pessário cervical na redução de partos prematuros em mulheres com colo curto. Há uma necessidade de mais estudos em diferentes contextos (os países desenvolvidos e em desenvolvimento), e com diferentes fatores de risco, incluindo a gestação múltipla.
Preterm birth (PTB), defined as birth prior to 37 weeks of gestation, occurs in ten percent of all pregnancies. PTB is responsible for more than half of neonatal and infant mortalities and morbidities. Because cervical insufficiency is a common cause of PTB, one possible preventive strategy involves insertion of a cervical pessary to support the cervix. Several published studies have compared the use of pessary with different management options and obtained questionable results. This highlights the need for an up-to-date systematic review of the evidence.
OBJECTIVES:
To evaluate the benefits and harms of cervical pessary for preventing preterm birth in women with singleton pregnancies and risk factors for cervical insufficiency compared to no treatment, vaginal progesterone, cervical cerclage or bedrest.
SEARCH METHODS:
We searched Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform to 22 September 2021. We also searched the reference lists of included studies for additional records.
SELECTION CRITERIA:
We included published and unpublished randomised controlled trials (RCTs) comparing cervical pessary with no treatment, vaginal progesterone, cervical cerclage or bedrest for preventing PTB. We excluded quasi-randomised trials. Our primary outcome was delivery before 34 weeks' gestation. Our secondary outcomes were 1. delivery before 37 weeks' gestation, 2. maternal mortality, 3. maternal infection or inflammation, 4. preterm prelabour rupture of membranes, 5. harm to woman from the intervention, 6. maternal medications, 7. discontinuation of the intervention, 8. maternal satisfaction, 9. neonatal/paediatric care unit admission, 10. fetal/infant mortality, 11. neonatal sepsis, 12. gestational age at birth, 13. harm to offspring from the intervention 14. birthweight, 15. early neurodevelopmental morbidity, 15. late neurodevelopmental morbidity, 16. gastrointestinal morbidity and 17. respiratory morbidity.
DATA COLLECTION AND ANALYSIS:
Two review authors independently assessed trials for eligibility and risk of bias, evaluated trustworthiness based on criteria developed by the Cochrane Pregnancy and Childbirth Review Group, extracted data, checked for accuracy and assessed certainty of evidence using the GRADE approach.
MAIN RESULTS:
We included eight RCTs (2983 participants). We included five RCTs (1830 women) in the comparison cervical pessary versus no treatment, three RCTs (1126 pregnant women) in the comparison cervical pessary versus vaginal progesterone, and one study (13 participants) in the comparison cervical pessary versus cervical cerclage. Overall, the certainty of evidence was low to moderate due to inconsistency (statistical heterogeneity), imprecision (few events and wide 95% confidence intervals (CIs) consistent with possible benefit and harm), and risk of performance and detection bias. Cervical pessary versus no treatment Cervical pessary compared with no treatment may reduce the risk of delivery before 34 weeks (risk ratio (RR) 0.72, 95% CI 0.33 to 1.55; 5 studies, 1830 women; low-certainty evidence) or before 37 weeks (RR 0.68, 95% CI 0.44 to 1.05; 5 studies, 1830 women; low-certainty evidence). However, these results should be viewed with caution because the 95% CIs cross the line of no effect. Cervical pessary compared with no treatment probably has little or no effect on the risk of maternal infection or inflammation (RR 1.04, 95% CI 0.87 to 1.26; 2 studies, 1032 women; moderate-certainty evidence). It is unclear if cervical pessary compared with no treatment has an effect on neonatal/paediatric care unit admission (RR 0.96, 95% CI 0.58 to 1.59; 3 studies, 1332 infants; low-certainty evidence) or fetal/neonatal mortality (RR 0.93, 95% CI 0.58 to 1.48; 5 studies, 1830 infants; low-certainty evidence) because the 95% CIs are compatible with a wide range of effects that encompass both appreciable benefit and harm. Cervical pessary versus vaginal progesterone Cervical pessary may reduce the risk of delivery before 34 weeks (RR 0.72, 95% CI 0.52 to 1.02; 3 studies, 1126 women; moderate-certainty evidence) or before 37 weeks (RR 0.89, 95% CI 0.73 to 1.09; 3 studies, 1126 women; moderate-certainty evidence), but we are uncertain of the results because the 95% CI crosses the line of no effect. The intervention probably has little or no effect on maternal infection or inflammation (RR 0.95, 95% CI 0.81 to 1.12; 2 studies, 265 women; moderate-certainty evidence). It is unclear if cervical pessary compared with vaginal progesterone has an effect on the risk of neonatal/paediatric care unit admission (RR 0.98, 95% CI 0.49 to 1.98; low-certainty evidence) or fetal/neonatal mortality (RR 1.97, 95% CI 0.50 to 7.70; 2 studies; 265 infants; low-certainty evidence) because the 95% CIs are compatible with a wide range of effects that encompass both appreciable benefit and harm. Cervical pessary versus cervical cerclage Only one very small study of 13 pregnant women contributed data to this comparison; the results were unclear.
AUTHORS' CONCLUSIONS:
In women with a singleton pregnancy, cervical pessary compared with no treatment or vaginal progesterone may reduce the risk of delivery before 34 weeks or 37 weeks, although these results should be viewed with caution due to uncertainty around the effect estimates. There is insufficient evidence with regard to the effect of cervical pessary compared with cervical cerclage on PTB. Due to low certainty-evidence in many of the prespecified outcomes and non-reporting of several other outcomes of interest for this review, there is a need for further robust RCTs that use standardised terminology for maternal and offspring outcomes. Future trials should take place in a range of settings to improve generalisability of the evidence. Further research should concentrate on comparisons of cervical pessary versus cervical cerclage and bed rest. Investigation of different phenotypes of PTB may be relevant.
