Now that you’re pregnant, you’re wise to start researching the various tests that are available so that you have plenty of time to decide what is right for you. Both CVS and Amniocentesis are tests that detect genetic problems in babies. The most common genetic disorder is Down Syndrome, which is also known as Trisomy 21.
Both tests are considered invasive, which means that there is a very slight risk of miscarriage from having the tests. There are a few basic differences in the tests. CVS samples the Chorionic Villus that eventually becomes the placenta. This is performed between 10 and 12 weeks and is 98 to 99% accurate. The risk of miscarriage ranges from 1 in 200 to 1 in 300. This test might be recommended for moms who would like to know about their baby’s health in the 1st trimester.
Amniocentesis is performed between 16 and 20 weeks and is over 99% accurate. With an amniocentesis, testing is done to determine whether there are spinal cord or other neural tube defects. The risk of miscarriage is about 1 in 300. This test might be recommended for moms who don’t mind waiting until the 2nd trimester for a little bit more information and slightly higher accuracy.
See also: Do I Need Genetic Testing?
I’m 36 years old and 6 weeks pregnant. I’ve heard about the CVS test and amniocentesis, but I’m not sure which test to take (or even if I need to do either one at all). What’s the difference? 
