In this case, amniocentesis may not be worth the risks. If you are interested in amniocentesis, talk with your clinician. Genetic counseling is available for parents who would like more help understanding the procedure and the possible test results. CVS cannot screen for open neural tube defects. During this test, a clinician inserts a thin plastic tube through the vagina and cervix and into the uterine cavity.
Chromosome analysis is done on cells from the tissue sample.
This prenatal test has been available in the United States only since 1983 and clinicians are still evaluating its safety and accuracy. Test results may be difficult to interpret and the risk of miscarriage is roughly twice that for amniocentesis. Also, there is a small risk that the mother might develop an infection in the uterus. And some recent studies link CVS with limb defects. Some couples would choose to carry the pregnancy to term regardless of the test results.