Abstract
Objectives
The most effective preterm birth (PTB) intervention is unknown for women who are at
risk of PTB due to a history of conization. The objective of this systematic review
was to determine whether PTB interventions, progesterone, cerclage, and pessary decrease
the risk of PTB compared to no treatment in singleton—and separately in twin—pregnancies
of women with history of conization.
Methods
We searched Cochrane Central, MEDLINE, EMBASE, CINAHL, and ClinicalTrials.gov from January 1994 until May 2017. In duplicate, we reviewed titles, abstracts, full
texts, extracted data, and assessed quality. We included RCTs and observational studies.
Our primary outcomes were PTB <34 weeks, PTB <37 weeks, and neonatal mortality. We
performed random effects meta-analyses and generated ORs with 95% CIs.
Results
We screened 762 nonduplicate titles and abstracts and assessed 91 full texts. After
contacting authors, we included nine studies. Women in the cerclage group were more
likely to have a short cervix or another risk factor for PTB, raising the possibility
of confounding by indication. In women with a history of conization and a singleton
who received a cerclage compared to those who did not, the ORs of PTB <34 weeks was
3.99 (95% CI 0.67–23.62, three studies, I2 = 65%); of PTB <37 weeks was 2.10 (95% CI 0.87–5.05, four studies, I2 = 0%); and of neonatal mortality was 8.33 (95% CI 0.22–320.38, two studies, I2 = N/A). We did not find any studies comparing either progesterone or pessary to no
treatment. Data for twins were very scarce.
Conclusion
In women with a previous conization and a current singleton gestation, the existing
evidence, which is likely limited due to confounding by indication, does not support
cerclage or other interventions used to try to decrease PTB.
Résumé
Objectifs
On ne sait pas quelle intervention est la plus efficace pour éviter les accouchements
prématurés chez les femmes à risque en raison d’une conisation antérieure. L’objectif
de cette revue systématique était de déterminer si les interventions, le cerclage
ou l’utilisation de progestérone ou d’un pessaire diminuent le risque d’accouchement
prématuré par rapport à l’absence de traitement dans les grossesses monofœtales –
ainsi que gémellaires, séparément – chez les femmes ayant subi une conisation.
Méthodologie
Nous avons fait des recherches dans les bases de données Cochrane CENTRAL, MEDLINE,
Embase, CINAHL et ClinicalTrials.gov de janvier 1994 à mai 2017. Nous avons analysé les titres, les résumés et les textes
complets, extrait les données et évalué la qualité deux fois. Nous avons inclus des
ECR et des études observationnelles. Nos issues primaires étaient l’accouchement avant
34 semaines, l’accouchement avant 37 semaines et la mortalité néonatale. Nous avons
effectué des méta-analyses à effets aléatoires et généré des rapports de cotes (RC)
avec des intervalles de confiance à 95 %.
Résultats
Nous avons relevé 762 titres et résumés uniques et évalué 91 textes complets. Après
avoir communiqué avec les auteurs, nous avons inclus neuf études. Les femmes dans
le groupe de cerclage étaient plus susceptibles de présenter un col de l’utérus court
ou un autre facteur de risque d’accouchement prématuré, ce qui augmentait la probabilité
de confusion par indication. Si on comparait les femmes ayant déjà subi une conisation
enceintes d’un seul fœtus qui avaient subi un cerclage à celles qui n’en avaient pas
subi, le RC d’accouchement avant 34 semaines était de 3,99 (IC à 95 % : 0,67–23,62;
trois études, I2 = 65%); celui d’accouchement avant 37 semaines était de 2,10 (IC à 95 % : 0,87–5,05;
quatre études, I2 = 0 %); et celui de mortalité néonatale, de 8,33 (IC à 95 % : 0,22–320,38; deux études,
I2 = s.o.). Nous n’avons pas trouvé d’études comparant l’utilisation de la progestérone
ou d’un pessaire à l’absence de traitement. Les données pour les grossesses gémellaires
étaient très limitées.
Conclusions
Chez les femmes enceintes d’un seul fœtus ayant déjà subi une conisation, les données
actuelles, qui sont vraisemblablement limitées en raison de la confusion par indication,
n’appuient pas le cerclage ni les autres interventions utilisées pour tenter d’éviter
les accouchements prématurés.
Key Words
Abbreviations:
17OHPC (17α-hydroxyprogesterone caproate), CIN (cervical intraepithelial neoplasia), GRADE (grading of recommendations assessment, development, and evaluation), LEEP (Loop electrosurgical excision procedure), LLETZ (large loop excision of the transformation zone), MD (mean difference), PTB (preterm birth)To read this article in full you will need to make a payment
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Article info
Publication history
Published online: October 26, 2018
Accepted:
April 12,
2018
Received:
January 10,
2018
Footnotes
Competing interests: The authors declare that they have no competing interests.
Identification
Copyright
Copyright © 2019 The Society of Obstetricians and Gynaecologists of Canada/La Société des obstétriciens et gynécologues du Canada. Published by Elsevier Inc. All rights reserved.
