Cervical Maturity Assessment Based on Ultrasound Elastography E-Cervix: Cluster Analysis.

OBJECTIVE

To identify distinct cervical remodeling phenotypes based on ultrasound and quantitative elastography parameters using cluster analysis.

METHODS

This single-center, prospective, observational study was conducted from February 2023 to January 2024 and included 373 pregnant women with singleton pregnancies between 6 + 0 and 41 + 0 weeks of gestation (total number of ultrasound examinations: 516). Cervical elastography was performed using the E-Cervix software (Samsung Medison, W10 system), with assessment of quantitative parameters (hardness ratio [HR], elasticity contrast index [ECI], internal os [IOS], external os [EOS]).

RESULTS

Correlation analysis demonstrated that cervical hardness (HR) decreased, while tissue heterogeneity (ECI) and internal and external os deformation (IOS, EOS) increased with gestational age and cervical shortening. Cluster analysis identified three cervical phenotypes: the "immature cervix" phenotype had the greatest cervical length (37.4 mm [interquartile range 36.3-38.4]) and highest stiffness (HR 76.7% [75.7-77.7]), while the "mature cervix" phenotype showed the shortest length (24.1 mm [22.9-25.4]) and lowest stiffness (HR 38.1% [36.9-39.3]). Bishop scores differed significantly among the clusters (4, 6, and 8, respectively). The risk of spontaneous labor within 14 days was highest in the mature cervix group (HR 10.1, P < .001).

CONCLUSION

Decreasing HR and increasing ECI, IOS, and EOS indicate progressive cervical softening as pregnancy advances and the cervix shortens. The combination of elastography parameters and cervical length can be used to objectively assess cervical remodeling during pregnancy.