Amniocentesis & CVS

The two tests differ mainly in timing and the type of tissue sampled:

• CVS (Chorionic Villus Sampling): Performed between 11 and 14 weeks. We take a tiny sample of the placenta. Because the placenta usually has the same genetic material as the baby, it provides an early diagnosis.
• Amniocentesis: Performed from 16 weeks onwards. We take a small amount (about 20ml) of the amniotic fluid surrounding the baby, which contains the baby's own skin and bladder cells.

Diagnostic testing is not mandatory for every pregnancy, but it is often recommended if:

• A screening test (like NIPT or NT scan) has shown a high-risk result.
• An ultrasound has detected a structural anomaly in the baby.
• There is a known family history of a specific genetic condition (like Thalassemia or Cystic Fibrosis).
• The parents are known carriers of a genetic mutation.

The actual procedure is quick and synchronized with ultrasound:

1. Ultrasound Mapping: We find a clear pocket of fluid (for amnio) or a clear path to the placenta (for CVS) away from the baby.
2. The Needle: A thin, high-precision needle is passed through the mother's abdomen. You will feel a quick pinch, similar to having a blood test.
3. Continuous Guidance: The needle is watched on the screen every second to ensure it remains in the safe zone.
4. Sample Collection: For amnio, we withdraw the fluid; for CVS, we take tiny pin-head sized pieces of placental tissue. The entire process takes less than 2 minutes.

After the procedure, we follow a strict safety protocol:

• Immediate Check: We show you the baby's heartbeat on the screen to provide immediate reassurance.
• Recovery: You will rest in our comfortable recovery suite for 20-30 minutes and should avoid heavy lifting for 24 hours.
• The Lab: The sample is sent to our specialized genetics partner for analysis.
• Results: A 'Rapid Result' (QF-PCR) for Down syndrome and other common conditions is usually ready in 48-72 hours. A full 'Microarray' or 'Exome' result takes 10 to 14 days.

The results from these tests are considered definitive.

• Clear Result: If the test is normal, it excludes almost all major chromosomal variations.
• Abnormal Result: If a condition is found, our team, including Dr. Leanne Bricker and our Clinical Geneticists, provides a detailed consultation to explain exactly what the result means for your baby's health and your options for care.

Deciding to have an invasive test can be emotional. At the MFM Unit, we prioritize 'Informed Choice.'

Before any procedure, you will have a detailed counseling session to discuss the 'Why' and 'How.' Our miscarriage risk rate is among the lowest in the world—estimated at 1 in 1,000 cases—because these procedures are performed exclusively by subspecialty consultants with decades of experience.