Cervical vascularization indices in the prediction of imminent preterm labor

Abstract

Objective: To establish the usefulness of cervical vascularization indices in the
prediction of impending preterm labor. Design: Case-control study. Institution:
"Dr. Urquinaona" Central Hospital, Maracaibo, Venezuela. Participants: Patients
with preterm delivery within 7 days (group A) and pregnant women with preterm
delivery beyond 7 days (group B). Methods: Pregnant women were evaluated using
transvaginal ultrasound and followed until delivery. Main outcome measures:
General characteristics, cervical vascularity indices (vascularity index, flow index
and vascularity / flow index), impending preterm delivery, and prognostic efficacy.
Results: A total of 350 patients were included, 75 women presented imminent
preterm labor (group A) and 251 patients were considered as controls (group B).
Patients in group A had significantly lower values of vascularization index and flow
index compared to group B (p = 0.0122 and p < 0.0001, respectively). Patients in
group B had significantly higher values of vascularization / flow index compared to
patients in group A (p = 0.0103). The three indices and the combination of these did
not show the ability to discriminate imminent preterm labor. Conclusions: Patients
with imminent preterm labor showed significant differences in the vascularization
indices compared to patients presenting preterm labor beyond 7 days of ultrasound
evaluation. However, they are not useful in predicting impending preterm labor.