Answers
Cervical Incompetence

• Image of the cervix in sagittal plane demonstrates spontaneous dilation of the cervical canal
• Second Image showed changing cervical length with transducer pressure
• Cervical length is the length of the closed cervix, normally >3 cm

Incompetent Cervix Stages

• Diagrams above show progressive funneling of the cervix: “Trust Your Ultrasound”
• Final stage is bulging membrances +/- fetal parts in vagina

• Bulging membrances shown above (“hourglass membranes”)
• Most cases of incompetent cervix are idiopathic, although there is an association with congenital anomalies, prior DES exposure, connective tissue disorders, and trauma [e.g., prior conization]