This is a series of screening tests for chromosomal anomalies that can be initiated as early as the 10th week of pregnancy and performed until delivery. The genetic DNA material from the pregnancy and fetus, which circulates in the mother's blood, is examined in a laboratory using a sample drawn from the mother's blood. This test is particularly useful for screening for trisomy 21 (Down syndrome), trisomy 13 and 18, as well as sex chromosome anomalies. Since there is no intervention in the pregnancy, it poses no harm to the fetus. Although the screening test largely indicates the risk of chromosomal anomalies, it is not a definitive diagnostic test.
