Chorionic Villus Sampling (CVS) is a prenatal diagnostic procedure used to detect genetic abnormalities in a developing fetus. During this procedure, a small sample of cells is taken from the chorionic villi, which are tiny projections found in the placenta. The sample is then analyzed for chromosomal abnormalities and genetic disorders.
CVS is typically performed between the 10th and 13th weeks of pregnancy. It is often recommended for women who have an increased risk of having a baby with a genetic disorder. This could be due to advanced maternal age, a family history of genetic conditions, or abnormal results from other prenatal screening tests like the
nuchal translucency scan.
The procedure can be performed in two ways:
transcervically or
transabdominally. In the transcervical approach, a thin tube is inserted through the cervix to reach the placenta. In the transabdominal approach, a needle is inserted through the abdomen to access the placenta. Both methods are guided by
ultrasound to ensure accuracy and safety.
While CVS is generally safe, it does carry some risks. These include a small risk of
miscarriage (about 1 in 100), infection, and Rh sensitization if the mother is Rh-negative. It is essential to discuss these risks with your healthcare provider to make an informed decision.
CVS is highly accurate, with a diagnostic accuracy rate of over 99% for many genetic conditions. However, it is important to note that while CVS can confirm the presence of a genetic disorder, it cannot predict the severity or specific symptoms the baby might experience.
CVS is recommended for pregnant women who are at higher risk for genetic abnormalities. This includes women over the age of 35, those with a family history of genetic disorders, and those who have had abnormal results from other prenatal tests. It is also an option for couples who are known carriers of genetic mutations.
After the sample is collected, it is sent to a laboratory for analysis. Results are typically available within one to two weeks. If a genetic disorder is detected, genetic counseling is often recommended to help the parents understand the implications and discuss options for the remainder of the pregnancy.
Conclusion
Chorionic Villus Sampling (CVS) is a valuable tool in the early detection of genetic disorders. While it carries some risks, its high accuracy makes it a crucial option for expectant parents at risk of having a child with a genetic condition. Always consult with your healthcare provider to determine if CVS is the right choice for your pregnancy.
