Cervical Length Measurement by Transvaginal Ultrasound at 20 to 24 Weeks Gestation and the Timing and Mode of Delivery

Abstract

Objective To study the relationship between midtrimester cervical length measurement on transvaginal ultrasonography and timing and mode of delivery. Materials and methods A total of 200 asymptomatic antenatal women at 20 to 24 weeks gestation were recruited. Cervical assessment with transvaginal ultrasound was performed using a 5 MHz transvaginal probe. Findings of cervical assessment were then correlated with the timing and mode of delivery. Chisquare test and Odd's ratios with 95% confidence intervals were used. Results Sixteen percent women delivered preterm. A cervical length of ≤ 30 mm had good specificity and NPV. At the cut-off value of 25 mm or less, sensitivity was 31.3%, specificity was 100%, PPV was also 100% and NPV was 88.4%. Increased cervical length on TVS (>40 mm) was associated with higher rate of cesarean section as compared to <40 mm (66% vs 34%) and this observation was statistically significant. Conclusion Cervical length measured by TVS at midtrimester is a useful and significant predictor of the gestational age at delivery and the mode of delivery. The high negative predictive value avoids unnecessary interventions, such as tocolysis or cerclage in high-risk pregnancies. How to cite this article Arora P, Maitra NK, Agarwal S. Cervical Length Measurement by Transvaginal Ultrasound at 20 to 24 Weeks Gestation and the Timing and Mode of Delivery. J South Asian Feder Obst Gynae 2012;4(1):22-24.