Presentations - Macon & Joan Brock Virginia Health Sciences at Old Dominion University

Ultrasound Indicated Cerclage in Women with Previous Late Preterm Birth

Poster #: 11
Session/Time: B
Author: Amira Elzarea
Mentor: Tetsuya Kawakita, MD
Co-Investigator(s): 1. Shaida Campbell, B.S., 2. Wave Hatton 3. Danielle Long 4. Maya Vishnia, MD 5. Lea Nehme, MD 6. Jerri Waller, MD 7. Tracey DeYoung, MD 8. Madison C. Collazo, MD 9. Monica A. Ethirajan, B.S. 10. Tetsuya Kawakita, MD, M.S.
Research Type: Clinical Research

Abstract

Introduction: Preterm birth, delivery before 37 weeks, is a leading cause of neonatal morbidity and mortality. The objective of this study is to explore the effectiveness of ultrasound cervical length screening in reducing preterm births in individuals with varying preterm birth histories (<34 weeks vs. 34-36 weeks) to optimize prevention strategies.

Methods: Study Design: A retrospective cohort study Setting: Single academic institution Population: Pregnant individuals with singleton pregnancies and a history of preterm birth from January 2014 to December 2020 who underwent transvaginal ultrasound cervical length screening. Primary Outcome: The primary outcome measure was the detection of a short cervix (≤25 mm) by transvaginal ultrasound. Methods: Serial cervical length screenings were performed biweekly from 16 to 24 weeks' gestation, and cerclage was recommended for cervical lengths ≤25 mm. Relative risks (RR) with 95% confidence intervals (95%CI) were calculated using modified Poisson regression with robust variance, controlling for confounders. Further, Kaplan Meier Survival Curves were plotted, and curves were compared using log-rank test.

Results: Of 576 individuals, 437 (75.9%) had a previous GA <34 weeks and 139 (24.1%) has a previous GA 34-36 weeks. Compared to individuals with a previous GA<34 weeks preterm births, those with a previous 34-36 weeks preterm births were less likely to have short cervix (41.9% vs. 21.6%; RR 0.52; 95%CI 0.37-0.73), ultrasound-indicated cerclage (21.1% vs. 6.5%; RR 0.34; 95%CI 0.18-0.67), and preterm delivery <34 weeks (20.8% vs. 6.5%; RR 0.32; 95%CI 0.17-0.64). However, based on our analysis of the Kaplan Meier Survival Curves, there was no significant difference in gestational age at delivery between groups (log-rank p = 0.75).

Conclusion: Individuals with a previous 34-36 weeks preterm births compared to those with a previous GA<34 weeks preterm births were less likely to have preterm birth related complications. Those with a previous 34-36 weeks preterm births may need less frequent cervical length screening.