Revisiting the short cervix detected by transvaginal ultrasound in the second trimester: why cerclage therapy may not help.
OBJECTIVE: The purpose of this study was to identify the risk factors that are associated with increased neonatal morbidity in patients who were treated for sonographic evidence of internal os dilation and distal cervical shortening during the second trimester.
STUDY DESIGN: From May 1998 to June 2000 patients between 16 and 24 weeks of gestation with the following sonographic criteria were randomly assigned to McDonald cerclage or no cerclage: internal os dilation and either membrane prolapse into the endocervical canal at least 25% of the total cervical length but not beyond the external os or a shortened distal cervix
RESULTS: Of the 135 patients, 20 patients declined randomization, and 2 patients were diagnosed with acute chorioamnionitis. Of the 113 patients remaining, 55 patients were randomly assigned to the cerclage group, and 58 patients were randomly assigned to the no cerclage group. There were 8 rescue cerclage procedures (4 in each group). Regression analysis showed that readmission for preterm labor, chorioamnionitis, and abruption were consistently associated with early gestational age at delivery and increased morbidity. Cerclage did not affect perinatal outcome.
CONCLUSION: The sonographic findings of second trimester internal os dilation, membrane prolapse, and distal cervical shortening likely represent a common pathway of several pathophysiologic processes. Use of cerclage does not alter any perinatal outcome variables. Increased neonatal morbidity in these patients appears to be associated with subclinical infection, preterm labor, and abruption.
Published In/Presented At
Rust, O. A., Atlas, R. O., Reed, J., van Gaalen, J., & Balducci, J. (2001). Revisiting the short cervix detected by transvaginal ultrasound in the second trimester: why cerclage therapy may not help. American Journal Of Obstetrics And Gynecology, 185(5), 1098-1105.
Obstetrics and Gynecology
Department of Obstetrics and Gynecology