Diagnostic tests either confirm or deny the existence of chromosomal abnormalities. Most women opt to complete genetic screening first to see if there is a risk before moving on to invasive diagnostic testing, but other women may choose to go ahead with these tests.
AFP or Quad Screen
At around week 15-20, you may complete an AFP or Quad Screen test. These diagnostic blood tests determine whether or not your baby has neural tube defects, Down Syndrome, or other chromosomal abnormalities.
If the AFP or Quad Screen confirmed abnormalities, your caregiver may suggest amniocentesis. This diagnostic test checks the number and arrangement of chromosomes by taking a sample of amniotic fluid.
Chronic Villus Sampling (CVS)
Chronic Villus Sampling is another diagnostic test that removes cells from the placenta. You may complete this test around weeks 10-13.