Interfering effect of maternal cell contamination on invasive prenatal molecular genetic testing.

In the case of Sanger sequencing, sensitivity to MCC was variable, while for MLPA, only high levels of MCC proved to be significant. Although the next-generation sequencing method was sensitive to low-level MCC, if MCC level is determined in parallel, accurate quantification of allelic ratios can help to interpret the diagnostic results. Knowledge of significant MCC levels allows correct prenatal diagnosis even if samples are not purely of fetal origin and repeated sampling can be avoided in many of the cases.