The value of cervical length and plasma proMMP-9 levels for the prediction of preterm delivery in pregnant women presenting with threatened preterm labor

OBJECTIVE: To assess the value of plasma proMMP-9 levels in predicting the progress of threatened preterm labor to true preterm labor and delivery within 7 days of presentation, along with the ultrasonographic measurement of cervical length. STUDY DESIGN: The study included sixty two pregnant women presented in the 2nd Department of Obstetrics and Gynecology of University of Athens at Aretaieion Hospital with threatened preterm labor. On subjects' presentation, cervical length was evaluated with transvaginal ultrasonography, plasma proMMP-9 levels were measured with the use of a solid phase enzyme immunoassay, and maternal characteristics (smoking, history of preterm delivery and parity) as well as the use of tocolytics were recorded. Subjects were followed up for premature delivery within 7 days. ROC analysis for plasma proMMP-9 levels was performed and logistic regression analysis was used for the evaluation of the prognostic effect of the parameters. RESULTS: The only significant predictors for establishment of true preterm labor and delivery within 7 days of presentation were cervical length (with cutoff value 15 mm: odds ratio=0.022, 95% CI=0.002-0.243, p=0.002) and plasma proMMP-9 (with cutoff value 67.15 ng/ml: odds ratio=0.035, 95% CI=0.003-0.388, p=0.006). The combination of the adopted proMMP-9 and cervical length cutoff values was characterized by a sensitivity of 90.9% and a specificity of 98.3% for predicting the progress to true preterm labor and delivery. CONCLUSION: Plasma proMMP-9 levels could possibly serve as a predictive factor for the progress of threatened preterm labor to true preterm labor and delivery within 7 days of presentation, along with the ultrasonographic evaluation of cervical length.