A New Second-Trimester Scoring System To Predict Preterm Birth

Abstract

Objective

To create a new scoring system for predicting preterm birth by incorporating second-trimester sonographic measurements, including cervical length, uterocervical angle, and lower uterine segment myometrial thickness, along with cervical dilation.

Method

This prospective study included 252 pregnant women who were admitted to a university-affiliated research hospital between 16 and 24 gestational weeks. Participants were followed and categorized into two groups: preterm birth group (n=40) and term birth group (n=212). Cervical length, uterocervical angle, and myometrial thickness were measured and the predictive role of these parameters for preterm birth was evaluated. A new scoring system was developed based on the identified cut-off values.

Results

A cervical length≤36.3 mm predicted preterm birth with 85% sensitivity and 73.1% specificity (p<0.001, AUC=0.831), while a uterocervical angle>102.1 degrees predicted it with 92.5% sensitivity and 54.3% specificity (p<0.001, AUC=0.767). Additionally, a myometrial thickness≤5.7 mm predicted preterm birth with 90% sensitivity and 37.4% specificity (p=0.002, AUC=0.634). A new scoring system score≥2 predicted preterm birth with 75% sensitivity and 89.6% specificity (p<0.001, AUC=0.871). In the validation group, a total score≥2 predicted preterm birth with 70.6% sensitivity and 90.4% specificity (p<0.001, AUC=0.826).

Conclusion

This scoring system, incorporating cervical length, uterocervical angle, myometrial thickness, and cervical dilatation, offers a potential alternative to digital cervical examination, a subjective method for predicting preterm birth.

Keywords

neonatology - evolution - perinatal

Publication History

Received: 17 June 2025

Accepted after revision: 16 January 2026

Article published online:
03 February 2026

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