Non-invasive retesting requires redrawing blood, and if the non-invasive test is high risk, further amniocentesis is needed without drawing blood.
1. Non-invasive retest: the first non-invasive did not have a clear meaning, need to do non-invasive retest for the second time, in this case and the first time the same blood test.
2. Amniocentesis: if after non-invasive DNA, check out the high risk, simple non-invasive DNA test high risk, can not be sure that is the fetus with chromosomal disorders, the need for amniocentesis to determine whether the fetus is suffering from chromosomal disorders more accurately. Amniocentesis does not require blood sampling, and amniotic fluid is extracted through ultrasound to determine the location of the placenta and fetus, avoiding the placenta and fetus.
Whether non-invasive retesting requires redrawing of blood needs to be individualized by the doctor according to the specific situation, so as to avoid misdiagnosis.