The chorionic villus sampling is an invasive prenatal diagnostic test.
This exam is performed when the pregnant woman has high risk factors associated to the development of fetal chromosomal abnormalities.
The chorionic villus sampling is performed between the 10th and 12th week of pregnancy and the specialist prescribes this invasive prenatal test in case of:
- Advanced maternal age (over 35 years);
- Family history of chromosomal abnormalities ;
- Previous children affected by chromosomal abnormalities;
- Positivity to prenatal screening tests.
Due to its invasivity, the chorionic villus sampling presents a risk of miscarriage up to 1%.
This test is performed inserting a needle into the belly of the pregnant woman to draw chorionic villus samples that contain child’s DNA. Villus analysis will give information about the genetic pool of the fetus detecting the eventual presence of chromosomal abnormalities.
In order to perform the test, an ultrasound study is required to determine with precision the position of the placenta.
In rare cases it may be necessary to repeat the sampling: this can happen if the sample taken is not sufficient to carry out the diagnostic tests.
After the exam, patients could manifest abdominal pains, bleeding or fever: in these cases it is important to consult the gynecologist.
For the 2 days following the exam, pregnant women should avoid any physical activity.
The results of chorionic villus sampling are delivered within 20 days and have a high diagnostic value. Analysis of chorionic villus can determine if the child has chromosomal abnormalities such as trisomy 21, trisomy 18 and sex chromosome aneuploidies.
If you are not at risk consult your gynecologist to avoid the risks of chorionic villus sampling with the prenatal test of next-generation AURORA.