cervical length
Ultrasound measurement of cervical length used to assess preterm birth risk.
Full Definition
Cervical length measurement is a transvaginal ultrasound assessment of the distance from the internal to external cervical os, typically performed between 16-24 weeks of gestation. This measurement is used to assess the risk of spontaneous preterm birth, with a cervical length less than 25mm considered abnormal and associated with increased preterm delivery risk. The measurement should be obtained with an empty bladder, gentle probe insertion, and visualization of the entire cervical canal. Serial cervical length measurements may be performed in high-risk patients, and short cervical length may indicate the need for interventions such as progesterone supplementation or cerclage placement.
Usage
Usage note: Measured in millimeters; not hyphenated when used as a noun phrase.
In Context
- "Transvaginal ultrasound revealed a cervical length of 18mm at 20 weeks gestation." — Ultrasound report
- "Serial cervical length monitoring was initiated due to the patient's history of preterm birth." — High-risk pregnancy management plan