Prediction of prolonged pregnancy in threatened premature labor – The usefulness of elastase in amniotic fluid

Abstract

 【Objective】To compare elastase in amniotic fluid with other indices for prolonged pregnancy.

 【Method】We examined the cervical length, maternal blood markers（WBC, CRP）, and amniotic fluid markers （elastase, glucose, LDH）among 622 singleton pregnant women complicated with threatened premature labor or a premature rupture of the membranes who underwent amniotic aspiration at our hospital from May 2013 to May 2018. We analyzed the accuracy of predicting the occurrence of labor within 7 days using ROC curves. The accuracy was compared using AUC.

 【Result】It was found that elastase in amniotic fluid and prolonged pregnancy were significantly negatively correlated with the Spearman’s correlation coefficient -0.528（P value ＜ 0.001） . For predicting the occurrence of labor within 7 days, the AUC of elastase in amniotic fluid was 0.79, which was the highest compared with the other indices. The AUC was even higher, at 0.857, in the group of women with no rupture of the membranes. A similar trend was observed in cases at 22-33 weeks of gestation.

 【Conclusion】Elastase in amniotic fluid can be a highly accurate index for predicting the occurrence of labor within 7 days.