A Study On The Relationship Of Premature Delivery And Cell-Free Fetal DNA In Maternal Blood And Fetal Fibronection In Vaginal Secreion

Objective: Explore the relationship of premature delivery and cell-free fetal DNA in maternal blood and fetal fibronectin in vaginal secretionMethods: 30 cases, bearing a male fetus by B-ultrasonic, of premature delivery and the cured threatened premature delivery in the hospital were selected as control group and 30 cases, bearing a male fetus by B-ultrasonic, of normal pregnancy as contrast group. The gestational ages of the two groups have no significant difference. SRY levels in maternal blood were quantified with PCR (QF-PCR), the concentration of fetal DNA with SRY gene therein being measured; and fetal fibronectin in vaginal secretion was measured. The difference of the concentration of fetal DNA and fetal fibronectin between the two groups were compared using variance analysis.Results: In-group comparison: Variance analysis and Chi-Square test: X~2=1.0890, p=0.5983. Q test indicates that the fetal DNA concentration of the threatened premature delivery is significantly higher than that of the contrast group, and the premature delivery significantly higher than the threatened premature delivery (at p＜0.001). The difference positive rate both between premature delivery cases and threatened premature delivery cases and between the premature delivery cases and the normal pregnant cases is very significant at P＜0.01; however, the difference between the normal pregnant cases and the threatened premature delivery cases is not significant at P＞0.05. The concentration of fetal DNA in the cases of expression of fetal fibronectin is significantly higher than in those whose fetal fibronectin were negtive.Conclusion: The concentration of the cell-free fetal DNA in maternal blood is highly correlated with the threatened premature delivery, and the fetal fibronectin in vaginal secretion is correlated with the concentration of the cell-free fetal DNA in maternal blood.