OBJECTIVE: To estimate the effectiveness of prophylactic and therapeutic cerclage by meta-analysis of randomized clinical trials.
DATA SOURCES: We searched the Cochrane Pregnancy and Childbirth Group specialized register of clinical trials (May 2002). Congress proceedings of international society meetings of fetal–maternal and reproductive medicine were searched by hand.
METHODS OF STUDY SELECTION: Meta-analysis of randomized clinical trials comparing cervical cerclage with expectant management during pregnancy was performed. Further clarification was sought from trial authors when required.
TABULATION, INTEGRATION, AND RESULTS: Six trials describing a total of 2175 women were analyzed. Prophylactic cerclage was compared with no cerclage in four trials. Pooled results failed to show a statistically significant reduction in pregnancy loss and preterm delivery rates, although a small reduction in births less than 33 weeks' gestation was seen in the largest trial (relative risk [RR] 0.75; 95% confidence interval [CI] 0.58 to 0.98). Cervical cerclage was associated with mild pyrexia, increased use of tocolytic therapy, and hospital admission but no serious morbidity. Two trials examined the role of therapeutic cerclage when ultrasound examination revealed a short cervix. Pooled results failed to show a reduction in total pregnancy loss, early pregnancy loss, or preterm delivery before 28 and 34 weeks in women assigned to cervical cerclage.
CONCLUSION: The effectiveness of prophylactic cerclage in preventing preterm delivery in women at low or medium risk for second-trimester pregnancy loss has not been proven. The role of cerclage in women whose ultrasound reveals short cervix remains uncertain.
The effectiveness of prophylactic cerclage to prevent preterm delivery in women at low or medium risk for midtrimster pregnancy loss is unproven.
Department of Obstetrics and Gynecology, University of Liverpool, Liverpool, United Kingdom.
Address reprint requests to: Andrew J. Drakeley, MD, Department of Obstetrics and Gynecology, University of Liverpool, Liverpool Women's Hospital, Crown Street, Liverpool L8 7SS, UK; E-mail: firstname.lastname@example.org.
Supported in part by the University of Liverpool, which supports the Cochrane Pregnancy and Childbirth Group. There was no external funding or conflict of interest.
The authors acknowledge the additional unpublished information provided by Drs. Sietske M. Althuisius and Orion A. Rust.
Received December 12 06, 2002. Received in revised form May 05 20, 2003. Accepted June 06 05, 2003.