The Chorionic Villus sampling is a test done on a pregnant woman to determine if she baby will have genetic disorders. Chorionic Villus sampling test can determine chromosomal irregularities such as trisomy 13, Turner syndrome and Down syndrome. The test can also determine whether the baby has a genetic disorder such as a sickle cell anemia. The results are 99 percent accurate. There is, however, a 1 percent chance of getting mosaicism. Mosaicism is a result of this test in which both normal and abnormal chromosomes are taken. In this case, the woman may choose to have other tests done.
The actual procedure

The doctor first numbs the abdomen with local anesthetic. The doctor then, under guidance of ultra sound, puts in a needle through the skin, muscle and uterine wall to the placenta and takes the tissue. The doctor may also go through the cervix and take out the placenta villus tissue. The tissue is then sent to the lab to be analyzed. After the test, light bleeding and cramping may occur for a day. The results generally come in between seven to ten days. If the baby has a defect, genetic counseling is provided or some women choose to terminate pregnancy. The risk of having Chorionic Villus Sampling is that one out of three hundred woman will have a miscarriage.