CELL-FREE DNA AT NORMAL PREGNANCY AND ANEMIA IN RELATION TO BMI.

The total cell-free DNA (cfDNA) in the blood of pregnant woman is represented by maternal and fetal fractions. Level of the fetal cfDNA can be used for prediction of pregnancy-related disorders, such as preeclampsia, intrauterine growth restriction and preterm labour. However, it remains unclear whether cfDNA concentration depends on body mass index (BMI) and blood composition. Aim of this study was to determine changes of the maternal and fetal cfDNA concentrations during pregnancy, as well as the influence of BMI and anemia. Fractions of cfDNA in maternal plasma were analyzed by means of methylation patterns in the promoter of the RASSF1A gene among 24 women at 11-14, 24-26, 30-32 weeks of pregnancy. Mean concentration of the maternal cfDNA was 14300,9±5294,1 GE/ml at 11-14 weeks, 13413,7±6187,4 GE/ml at 24-26 weeks and 13902,7±6526,0 GE/ml at 30-32 weeks (p>0.05). Mean fetal cfDNA levels at 11-14 and 24-26 weeks were similar (1265,1±577,5 and 1309,1±561,0 GE/ml), respectively. At 30-32 weeks mean concentration of fetal cfDNA was significantly higher than at 11-14 and 24-26 weeks (1742,0 GE/ml) (p<0,05). There was no correlation between maternal or fetal cfDNA concentrations and BMI at pregnancy. Further, the pregnant women were divided into 2 groups: with (11) and without anemia (13). Fetal cfDNA concentration did not differ between groups. However, maternal cfDNA concentration at 24-26 and 30-32 weeks was significantly lower in anemic women compared to healthy women, 12607,1±6923,9 versus 14096,3±5685,5 GE/ml and 11761,4±4976,3 versus 15714,6±7296,1 GE/ml, respectively (p<0,05). Thus, concentration of the maternal cfDNA remains stable during pregnancy. The fetal cfDNA concentration remains relatively stable up to 24-26 weeks of gestation, but than significantly increases by 30-32 weeks. Levels of maternal and fetal cfDNA do not vary with maternal BMI. Maternal cfDNA levels are significantly lower in women with anemia. [ABSTRACT FROM AUTHOR]