Universal Transvaginal Ultrasounds: Does It Really Make a Difference? [ID: 1369458

Abstract

INTRODUCTION: There are no universal guidelines for transvaginal ultrasound (TVUS) at time of anatomy scan. TVUS can provide valuable information on placental location and cervical length (CL). As a quality assurance initiative, universal TVUS (UTVUS) protocol was started. The aim of this study was to evaluate differences in diagnoses and interventions in the 6 months prior to UTVUS protocol to 6 months after implementation. METHODS: This was an institutional review board-approved retrospective cohort study performed on singleton gestations from February 2021 to January 2022. The pre-group underwent TVUS for history of preterm birth, if the cervix appeared short or if the placenta appeared low lying on transabdominal scan. In the post-group, all patients underwent TVUS. RESULTS: Of the 1,197 patients, 148 underwent TVUS in the pre-group and 1,049 received UTVUS in the post-group. A greater proportion of patients had short CL identified in the post-group compared to the pre-group (2.2% versus 0.9%, P<.01). Additionally, CL was shorter in the post-group compared to the pre-group (median 1.6 versus 2.2 cm, P=.03). A greater proportion of patients in the post-group received vaginal progesterone (3.1% versus 0.7%, P<.01) and cerclage (2.3% versus 0.7%, P<.01) compared to those in the pre-group, and had a later gestational age at cerclage placement (median 17 weeks 2 days versus 13 weeks 6 days, P=.04). Patients in the pre-group had a higher rate of prior preterm birth (P<.01), delivered at an earlier gestational age (P<.01), and were more likely to have neonatal intensive care unit admission compared to patients in the post-group (P=.02). The overall preterm birth rate in both time periods was not significantly different (11.4% versus 11.2%, P=.82). CONCLUSION: UTVUS identifies shorter CL, which leads to increased use of vaginal progesterone and cerclage as compared to abdominal ultrasound with targeted TVUS. UTVUS may lead to increased intervention. However, the cost-effectiveness and clinical significance need to be further evaluated.