Related Experiment Video
Updated: Nov 21, 2025

Mouse Model of Surgical Uterine Injury and Subsequent Pregnancy Outcomes
Published on: June 27, 2025
Universal transvaginal cervical length screening during pregnancy increases the diagnostic incidence of low-lying
Samantha Sinclair1, Heather R Masters1, Emily DeFranco1
1Department of Obstetrics and Gynecology, University of Cincinnati College of Medicine, Cincinnati, OH.
Background:
Universal transvaginal cervical length screening has been increasingly implemented with both positive and negative consequences.
Objective:
In this study, we described the diagnostic incidence of low-lying placenta and placenta previa with the implementation of universal transvaginal cervical length screening.
Study Design:
This is a retrospective cohort study of women undergoing midtrimester universal transvaginal cervical length screening. The primary outcome was the rate of transvaginal diagnosis of low-lying placenta or placenta previa using midtrimester universal transvaginal cervical length screening.
Results:
This study included 1982 midtrimester ultrasounds, of which 211 indicated a low-lying placenta or placenta previa on either transabdominal or transvaginal ultrasound. With transvaginal ultrasound, a low-lying placenta or placenta previa was diagnosed in 211 women (10.6% of the study population). Of the 211 patients with a low-lying placenta or placenta previa, 90 (42.6%) had a false-negative result, diagnosed using only transvaginal ultrasound; 112 (53.1%) had a true-positive result; and 9 (4.3%) had a false-positive result. The relative risk of having an abnormal finding on ultrasound with the addition of universal transvaginal cervical length screening was 9.2 (95% confidence interval, 4.6-18.1). Of the low-lying placenta or placenta previa diagnosed using midtrimester universal transvaginal cervical length screening, 98.9% resolved (95% confidence interval, 93.7-99.97).
Conclusion:
Implementation of universal transvaginal cervical length screening increases the diagnostic incidence of low-lying placenta or placenta previa without an increase in the diagnoses that persist to term, which comes at the cost of increased follow-up ultrasounds and potentially increased anxiety for the patient.

