Ultrasonography is the principal modality of the diagnosis during pregnancy (transabdominal, transperineal or transvaginal), MRI appearance of the cervical incompetence may demonstrate a higher degree of soft tissue contrast than ultrasonography.
Differential diagnosis: Other causes of preterm labor (PROM, chorioamnionitis , uterine contractility) .
Management: In patients at risk for pregnancy loss, placement of cervical cerclages in response to sonographic detected shortening of the endocervical canal length is an acceptable alternative to the use of elective cerclage.
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