Abstract
Objective: To explore the concentrations of matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of metalloproteinase-1 (TIMP-1) in plasma, serum and urine of women during term and threatened preterm labor. Methods: Plasma and urine proMMP-9 as well as serum and urine TIMP-1 were evaluated in 60 healthy pregnant women; 20 of them presented in term labor following an uncomplicated pregnancy, 20 of them presented with threatened preterm labor and intact membranes at 24-36 gestational weeks and 20 of them were at 24-40 gestational weeks with no evidence of uterine contractions or other pregnancy complications. Data were analyzed with non-parametric statistical tests and cut-off values were determined with receiver operator characteristic curves. Results: ProMMP-9 values were significantly higher and TIMP-1 values were significantly lower in cases with uterine term or preterm contractions compared to non-labor status; and in cases with preterm contractions that progressed to true preterm labor compared to those in which contractions were arrested. Conclusions: Alterations in the concentrations of proMMP-9 and TIMP-1 can be detected in plasma or serum and urine of pregnant women experiencing term or preterm uterine contractions. The altered values of proMMP-9 and TIMP-1 could possibly identify the inevitable progress of preterm contractions to true preterm labor.