Book Appointment

What is CVS (Chorionic Villus Sampling) and How Does It Detect Genetic Disorders?

What is CVS (Chorionic Villous Sampling)?

Chorionic villous sampling (CVS) is a prenatal test. It checks for genetic or chromosomal problems in a developing baby. Doctors often use CVS early in pregnancy. Because it gives important information, many parents want to know more about this test. CVS helps find certain health conditions before birth. According to the CDC, CVS is a safe and common test for early pregnancy screening.

Why is CVS Performed?

Doctors may suggest CVS for several reasons. For example, if a parent has a family history of genetic disorders, CVS can help. Sometimes, screening tests show a higher risk for certain conditions. In these cases, CVS can give a clear answer. The test can detect:

  • Down syndrome
  • Cystic fibrosis
  • Tay-Sachs disease
  • Sickle cell anemia

    • Because CVS gives early results, parents can make informed choices sooner.

    How is CVS Done? (Procedure Overview)

    CVS is usually done between 10 and 13 weeks of pregnancy. First, the doctor uses ultrasound to find the placenta. Then, a small sample of tissue is taken from the placenta. This tissue is called chorionic villi. There are two main ways to collect the sample:

  • Transabdominal: A thin needle goes through the belly into the placenta.
  • Transcervical: A thin tube goes through the cervix to the placenta.

    • After the sample is collected, it is sent to a lab for testing. The whole CVS procedure in pregnancy usually takes less than 30 minutes. Most women can go home the same day.

    Who Should Consider CVS?

    Not everyone needs CVS. However, some people may benefit from this test. You may consider CVS if:

  • You are over 35 years old
  • You or your partner have a known genetic disorder
  • Previous tests show a higher risk for genetic problems
  • You had a child with a genetic condition before

    • Always talk to your doctor about your personal risks and needs. They can help you decide if CVS is right for you.

    Risks and Benefits of CVS

    Like any medical test, CVS has both risks and benefits. It is important to know both before making a decision.

  • Benefits: CVS gives early and accurate results. It helps parents plan for their baby’s care. The test can detect many genetic conditions.
  • Risks: There is a small risk of miscarriage (about 1 in 100). Some women may have cramping or light bleeding. Rarely, infection or injury can occur. According to the WHO, CVS is generally safe when performed by trained doctors.

    • Because CVS risks are low, many parents choose this test for peace of mind.

    Preparation and Aftercare

    Before the test, your doctor will explain what to expect. You may need to have a full bladder for the procedure. Wear comfortable clothes on the day of the test. After CVS, you should rest for the next 24 hours. Avoid heavy lifting or strenuous activity. If you have severe pain, fever, or heavy bleeding, call your doctor right away. Most women recover quickly and have no lasting problems.

    Frequently Asked Questions About CVS

  • Is CVS painful? Most women feel mild discomfort, but the test is usually quick.
  • How soon will I get results? Results are often ready in one to two weeks.
  • Can CVS detect all birth defects? No, CVS mainly checks for genetic and chromosomal problems.
  • Is CVS safer than amniocentesis? Both tests have similar risks, but CVS is done earlier in pregnancy.

    • When to Consult a Fetal Medicine Specialist

    If you have questions about CVS, it is best to talk to a fetal medicine specialist. They can explain the CVS test benefits and risks for your situation. If you have a family history of genetic problems, or if your doctor suggests CVS, a specialist can guide you. Early advice helps you make the best choice for your family.

    Consult a fetal medicine specialist for personalized advice about CVS (chorionic villous sampling).