FREE EMBRYONIC DNA IN PLASMA AS A PREDICTOR OF SPONTANEOUS PREGNANCY LOSSES IN WOMEN WITH RECURRENT MISCARRIAGE

Objective. To reveal an association between the plasma levels of free embryonic DNA (feDNA) in the first trimester of pregnancy and recurrent miscarriage before 22 weeks’ gestation. Subjects and methods. A study group included 122 women with recurrent miscarriage and a control group comprised 103 pregnant women without obstetric and gynecological histories. The levels of feDNA (SRY and DYS-14 genes) were determined in the first trimester of pregnancy by real-time polymerase chain reaction. In 44 patients, the study was conducted over time at 6 to 20 weeks’ gestation at a 2-week interval. Results. There was a significant excess of feDNA levels in the women with recurrent miscarriage as compared to those with uncomplicated pregnancy (DYS-14, 1021.0±660.6 versus 172.4±56.8 copies/ml; p<0.01; SRY, 124.4±48.3 versus 45.3±21.6 copies/ml;p<0.01). The women with recurrent miscarriage were found to have the rise in DYS-14 and SRY levels at 6 to 20 weeks’ gestation, which was greater than those in the control group (p<0.05). Comparison of feDNA DYS-14 levels in the women whose pregnancy ended in spontaneous abortion before 22 weeks’ gestation versus in those who gave birth to full-term babies showed significant differences (1697.5±980.7 and 841.8±394.8 copies/ml, respectively; р<0.0001). The similar indicators for the SRY gene were 174.077±49.616 and 108.2±37.8 copies/ml (р<0.0001). Conclusion. In the pregnant woman, the plasma feDNA release up to the levels much greater than those in physiological pregnancy can serve as a predictor of spontaneous abortion before 22 weeks’ gestation.

recurrent miscarriage, DNA, prenatal diagnosis