Testing for Down Syndrome and Other Abnormalities in Early Pregnancy

For Women Under 35:
Triple Screen--This is a blood test that is done between 15 and 20 weeks. The test screens for Down syndrome and spina bifida, two common birth defects. The test is usually covered by insurance, and the results usually return 2 weeks after the blood draw.
Level II Ultrasound--This test takes pictures of your baby through an ultrasound on your tummy. It is done by a specialist at 18 to 22 weeks. An ultrasound can be used to detect anatomic problems with the baby, including if the heart and brain are not formed normally. It does not detect all birth defects. Insurance may cover this test; if not, it usually costs about $150.
First Trimester Screening--This test, done at 12 weeks, combines an ultrasound to look at the area of the baby's neck (nuchal translucency) with a blood test to detect Down syndrome and other chromosomal abnormalities like Trisomy 18. It detects 90 percent of the cases of Down syndrome. This test is done by a perinatologist, a high-risk obstetrics doctor or maternal fetal specialist, and is not yet considered the standard of care, and therefore may not be covered by insurance. It costs about $500.

For Women Over 35:
Because genetic birth defects are more common in women over 35, other testing is available. Women may receive the triple screen, ultrasound or first trimester screening as described above but slightly more invasive testing may also be recommended. This includes one of the following two tests:
Amniocentesis--In this test, a specialist uses a needle through your abdomen to remove fluid around the baby. The fluid is sent to a lab, where the genetic material of the baby is analyzed. This test is 99 percent accurate in detecting Down syndrome. It carries a risk of miscarriage of 0.4 percent. The test is done between 16 and 20 weeks and the results are given in 2 weeks.
Chorionic Villus Sampling (CVS)--A specialist uses a tube through the vagina and cervix or through the abdomen to remove cells from the baby's placenta. The tissue is sent to the lab, and this test detects 99 percent of Down syndrome cases. It carries a risk of miscarriage of 0.8 percent. The test is done between 10 and 13 weeks and results are available in 3 days.