Combination of biochemical markers in predicting pre-term delivery.

Purpose The aim of this study was to evaluate the predictive performances of some biochemical markers in predicting pre-term delivery in asymptomatic women. Methods We included 491 asymptomatic women at 24 weeks' gestation, who underwent the endocervical phosphorylated insulin-like growth factor binding protein (phIGFBP-1) test, cervico-vaginal interleukins 6 (IL-6) and 8 (IL-8), and serum C-reactive protein (CRP). A receiver-operating characteristics (ROC) curve was used to determine the most useful cut off point. A multivariate logistic regression model was used in order to analyze the combination of significant predictive variables for pre-term delivery following univariate analysis. Results ROC curves indicated that 33 mu g/l was the optimal cut off value for phIGFBP-1 test, 21.3 ng/l for IL-6, 324 ng/l for IL-8, and 8.42 mg/l for CRP in predicting preterm delivery. The univariate logistic regression analyses revealed an odds ratio of 3.04 for phIGFBP-1 test, 4.82 for IL-6, and 3.08 for CRP. The multivariate analysis of phIGFBP-1 test, IL-6, and CRP showed that they were independent variables and therefore useful in combination for predicting pre-term delivery. Conclusions The phIGFBP-1 test, the cervico-vaginal IL-6, and the serum CRP are independent variables that can be used together to predict pre-term delivery in asymptomatic women.