What is Amniocentesis and Do I Need One if I’m Pregnant?

Amniocentesis is a test done on pregnant women to check the health of their baby. It involves taking a small sample of the amniotic fluid, the liquid around the baby.

This fluid has material like fetal cells that can provide important information about the baby’s condition. During amniocentesis, the doctor uses a needle to take a sample of amniotic fluid to study it for signs of birth defects since the fluid can contain some of the baby’s cells.

When is Amniocentesis Performed?

Amniocentesis is usually used to diagnose genetic birth defects. This means it can be useful if you have a high risk of having a child with a genetic condition.

 You might be at high risk if you:

• Were pregnant with other children with genetic conditions or chromosomal abnormalities
• Have a family history of genetic birth defects
• Are 35 or older
• Have had a prenatal screening test that indicates a high risk of a genetic condition
• Have had ultrasounds indicating potential genetic conditions

Not all pregnant women need to get an amniocentesis. But your doctor may recommend it if you meet one or more of the aforementioned risks. It may also be needed if you’ve had a similarly complex pregnancy before.

What are Common Genetic Conditions?

The common genetic conditions that amniocentesis tests for are:

• Down syndrome
• Edward syndrome
• Patau syndrome

Because amniotic fluid contains parts of the fetus’ DNA, amniocentesis allows a doctor to look at fetal DNA in the fluid to see how many of each chromosome the fetus has. 

Amniocentesis can also diagnose cystic fibrosis, neural tube defects, sickle cell disease, and other fetal abnormalities and genetic conditions.

Common Indications for Amniocentesis

Amniocentesis is a versatile procedure and can be performed for many different reasons. Some of the most common ones are:

• Diagnosing chromosomal abnormalities like Down Syndrome
• Diagnosing other genetic conditions like neural tube defects
• Diagnosing infections in the fetus 
• Diagnosing infections in the amniotic fluid and placenta
• Determining fetal lung development and maturity (Note: It is crucial to test for fetal lung maturity if your baby needs to be delivered early)
• Diagnosing Rh disease

How Does Amniocentesis Work?

Amniocentesis is an outpatient procedure usually performed between 15 and 20 weeks of pregnancy. The steps involved in amniocentesis are the following:

1. Before the procedure, the doctor will perform an ultrasound to determine the position of the fetus and placenta.
2. The doctor will disinfect your skin and begin another ultrasound to monitor the procedure.
3. They will insert a syringe into your abdomen and through to the amniotic sac, possibly causing some discomfort or pain.
4. The ultrasound will help the doctor ensure the needle does not come into contact with the fetus or the placenta.
5. The doctor will use the syringe to take an amniotic fluid sample and remove the needle.
6. The amount of amniotic fluid taken will depend on the conditions the doctor will test for.
7. After the fluid is drawn, the doctor will check the fetus’ heartbeat and movement to ensure its condition is normal.

Amniocentesis can cost around $4,000. However, this price varies greatly depending on location and insurance coverage.

What are Recovery and Post-Procedure Care Like?

After amniocentesis, you will be monitored for some time. During this time, you can experience some cramping, similar to menstrual cramps, and light vaginal bleeding or spotting. 

These are normal and should resolve a few hours after the procedure. You can take paracetamol to help with the pain, but ibuprofen or aspirin should be avoided.

After amniocentesis, keep an eye out for vaginal bleeding, severe pain, fever, or leaking vaginal fluid, as amniotic fluid can leak from the vagina after amniocentesis. If you experience any of these, be sure to consult your doctor.ave no other risk factors for miscarriage.

Do I Need Bed Rest After Amniocentesis?

No, bed rest is not necessary after amniocentesis. Generally, you should be able to go about your day normally, but it is best to avoid strenuous physical activity for the rest of your day after the procedure.

Remember to monitor how you feel after the procedure to minimize the risk of pregnancy loss. Keeping your healthcare provider in the loop is also important.

What are the Risks of Amniocentesis?

Amniocentesis is generally considered to be a safe procedure. However, like with any medical procedure, there is still a risk of complications.

These include:

• Bleeding
• Cramps
• Amniotic fluid leaking from the vagina or the abdomen where the needle was used
• Infections
• Preterm labor

Is Amniocentesis Safe for the Baby?

There is a low risk of miscarriage as a result of amniocentesis. This risk can be less than 1% if you have no other risk factors for miscarriage.

Some diseases, like HIV, can be transferred from the parent to the child during amniocentesis. If you have HIV, you should start taking antiretroviral drugs before undergoing amniocentesis. Reducing the viral load through medication lowers the risk of transmission to the fetus.

If you are taking blood thinners, you should stop taking them for two to three days before the procedure. Your doctor might need to temporarily alter your prescription if you take blood thinners and require amniocentesis.

What if Amniocentesis Results are Positive?

Positive amniocentesis results mean your child will be born with a genetic or chromosomal condition. While receiving positive amniocentesis results can be difficult, it can also prompt early meetings with relevant experts. 

Disability experts, geneticists, and others can help you interpret your results, what they mean for you and your child, and how to best manage the pregnancy going forward. This can mean making arrangements to properly accommodate the child or the decision to terminate the pregnancy.

How Accurate Is Amniocentesis for Down Syndrome?

Amniocentesis is extremely accurate when it comes to diagnosing Down Syndrome. An amniocentesis result will be accurate almost 100% of the time. However, amniocentesis can’t detect all genetic disorders.

Why Amniocentesis is Better Than Ultrasound?

Ultrasound is essential for monitoring the health of the fetus during pregnancy. It can even detect potential genetic disorders by looking at the amount of fluid behind the neck of the fetus.

However, when it comes to genetic disorders like Down syndrome, ultrasound findings are not definitive. Further tests like amniocentesis will be necessary to diagnose the condition.

Amniocentesis vs. Other Prenatal Tests

There are two other prenatal tests that are commonly performed. Chorionic Villus Sampling (CVS) and non-invasive prenatal testing (NIPT).

• NIPT – A non-invasive test that requires taking a sample of your blood. Instead of a positive or negative result, NIPT can tell you if the fetus has an increased risk of being affected by a genetic disease. 
• CVS – An invasive program used to diagnose genetic conditions. It involves taking a sample of the placenta instead of the amniotic fluid. It’s typically performed from 11 to 14 weeks.