Longitud cervical en el segundo trimestre por ecografía transperineal para la predicción de parto pretérmino

Objective

To establish the prognostic usefulness of cervical length values in the second trimester using transperineal ultrasound for the prediction of preterm delivery.

Material and methods

A case-control study was conducted on a sample of 613 pregnant women attending the Hospital Central “Dr. Urquinaona”, Maracaibo, Venezuela. Group A consisted of 52 patients who had preterm deliveries and group B 561 pregnant women who had term deliveries, and considered as controls. An evaluation was made of the general characteristics of the patients, as well as of the cervical length values measured by transperineal ultrasound.

Results

The mean gestation age at the time of measuring the cervical length by transperineal ultrasound was 25.7 ± 1.2 weeks in group A, and 26.0 ± 1.1 weeks in group B (P = ns). There were no significant differences in maternal age, body mass index and history of preterm labour (P = ns). Values of cervical length measured by transperineal ultrasound were higher in group A (3.2 ± 0.4 centimetres) than in group B (4.0 ± 0.4 centimetres; P < .0001). A cut-off value of 3.5 centimetres had a value under curve of 0.88 with a sensitivity of 71.1%, specificity of 86.8%, and positive predictive value of 33.3%, and negative predictive value of 97.0%. Diagnostic accuracy was of 85.9%.

Conclusion

Cervical length in second trimester by transperineal ultrasound could be a useful tool for the prediction of preterm delivery.