Poly-sialylated glycan of cervicovaginal fluid can be a potential marker of preterm birth.

Preterm birth is a global health issue associated with neonatal death and morbidity. However, current methods of predicting preterm birth are insufficient to accurately screen for risk. This study aimed to assess the potential of site-specific N-glycosylation of cervicovaginal fluid (CVF) proteins as predictive biomarkers of preterm birth in a case-control study. Statistical analysis used Student's t-tests, ROC curve and logistic regression adjusted age and BMI. Using N-glycoproteomic analysis of the CVF, we identified 862 N-glycoproteins in CVF samples form 20 pregnancies and 6595 N-linked glycopeptides used a false discovery rate of less than 1%. Of 173 upregulated glycan in preterm group, we found low levels of fucosylation and high levels of sialylation in preterm birth (p < 0.05). Then we found that three poly-sialylated glycans had a high predictive value (AUC = 0.802, p < 0.017), which were expressed in all samples. In addition, the glycan model with clinical markers performed better. The results indicate that poly-sialylated glycans in CVF have potential value as novel clinical markers for predicting preterm birth during pregnancy. This study suggests strategies for developing new predictive biomarkers using cervicovaginal glycans to detect preterm birth in advance.