Predictive value of aspartate aminotransferase and alanine aminotransferase levels in vaginal fluid for the diagnosis of premature rupture of membranes

Background: Preterm premature rupture of membranes (PPROM) occurs in 3% of pregnancies and 30-40% of preterm labors are related to this problem. Early diagnosis of PPROM is very important due to its impact on pregnancy outcomes. Objective: To determine the diagnostic value of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels in vaginal fluid for the diagnosis of preterm premature rupture of membranes as a non-invasive and available test. Materials and Methods: A total of 148 pregnant women between the 26(th)-36(th) gestational weeks were enrolled in the study. 74 patients were in PROM group and 74 in control group. AST and ALT levels in vaginal fluid were measured in each group. Mann Whitney U-test was used to compare AST and ALT levels in each group. Results: The mean of AST level in vaginal fluid was 12.77±10.06 in PROM group vs. 6.91±10.92 in control group (p<0.001), while there were no significant difference between ALT levels in PROM group 1.51±3.17 and control group 0.89±1.15 (p=0.49). Optimal cut point of AST for the diagnosis of PROM was 4.5 IU/L in this study. The sensitivity, specificity, positive and negative predictive values were 82.4%, 63.5%, 69.32% and 78.33% respectively. Conclusion: According to the findings of this study, measurement of AST level in vaginal fluid can be used as a reliable test for diagnosis of PROM, but there is no good cut point for ALT level that can be practically used.