If you come across the term CVS test you should know that this is a kind of testing meant to find the chromosomal abnormalities and other disorders that could be inherited. The doctors usually recommend this testing to the couples who have some family history that reveals risks.
How is the CVS screening performed?
This is a diagnostic procedure during which the specialist removes some chorionic villi cells that can be found on the placenta from the region where the placenta is connected to the uterus. There are two main ways to collect the sample. First of all, there is the transcervical option.
In this case to perform the screening of CVS there is an ultrasound guided catheter that travels through the vagina all the way to the placenta. The cells are collected through gentle suction. Usually the doctors prefer this method. Secondly, there is also the option of the transabdominal procedure.
In this case of chorionic villus sampling test there is an ultrasound guided thin needle that penetrates the abdomen to the placenta. The doctor uses the needle to draw a sample and then removes the needle. This is something like amniocentesis. The difference is that in this case the sample is bigger and you get the results faster.
When is the test of chorionic villus sampling performed?
In the majority of the cases the doctors suggest women to have the test between weeks 10 and 13 from their last menstrual period. It is possible that this testing will be chosen over amniocentesis since it can be done earlier during pregnancy.
What does the chorionic villus sampling testing test for?
As it has been mentioned before, the main point of the testing is to recognize the chromosomal abnormalities such as Down syndrome and also the genetic disorders like cystic fibrosis. The test is different from amniocentesis because it canâ€™t offer information regarding neural tube defects.
During the testing of chorionic villus sampling the doctors gain access to the DNA of the baby that can be used for paternity testing even before the baby gets born. If you would like to determine paternity you should know that the results are 99% accurate.
What do the results mean?
In case of the chorionic villus sampling screening you will know if the baby has genetic disorders or chromosomal abnormalities with an accuracy of 98%-99%. Although the test can identify the problems, it cannot measure their severity. Also, as it has been mentioned before, it cannot detect the neural tube defects.
Risks and side effects
You should know that the screening of chorionic villus sampling is considered to be safe. However it is still an invasive test that comes with some risks. One of the most important risks is miscarriage. This occurs in about 1% of all the cases. The test isnâ€™t recommended to women who have STDs, twins or that experienced some vaginal bleeding.
Now you know a lot more about CVS testing and you can see that it could be very helpful.