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Coding and billing for transvaginal ultrasound to assess second trimester cervical length

Overview: Transvaginal ultrasound cervical length (TVU CL) assessment is a safe, acceptable, reproducible, and accurate screening test, with potentially widespread availability. However, both proponents and opponents of universal cervical length (CL) screening for increased prematurity risk raise valid issues. Cervical length screening for singleton gestations with or without a prior history of preterm birth is a reasonable strategy. Therefore, implementation of routine second-trimester TVU CL can be a reasonable screening method considered by individual practitioners. Third-party payors should not deny reimbursements for this screening.N/A



  • Sonographic assessment of CL should be performed only by individuals trained in the technique. 
  • A TVU CL assessment needs to be performed with proper technique, quality control, and monitoring to yield accurate results. To ensure quality, more information is available at CLEAR: Cervical Length Education and Review (
  • When performed in low-risk, asymptomatic women for purposes of preterm birth (PTB) screening, a single TVU CL determination obtained between about 18 weeks’ and 24 weeks’ gestation is sufficient. Serial cervical exams are usually not indicated in low-risk women, they areappropriate in high-risk pregnancies (ie, singleton gestations with prior PTB).
  • TVU is the preferred approach for diagnosing cervical shortening.
  • Payment for a single TVU examination performed between 18 and 24 weeks’ gestation for CL assessment in low risk patients (ie, singleton gestations without prior PTB) is appropriate. When screening high-riskpatients, a series of TVU CL measurements can be performed every 2 weeks between 16 and 24 weeks.