How accurate is an amniocentesis for Down syndrome?

How accurate is an amniocentesis for Down syndrome?

The diagnostic procedures available for prenatal diagnosis of Down syndrome are chorionic villus sampling (CVS) and amniocentesis. These procedures, which carry up to a 1% risk of causing a spontaneous termination (miscarriage), are nearly 100% accurate in diagnosing Down syndrome.

Can amniocentesis cause Down syndrome?

Problems detected by amniocentesis Amniocentesis can detect a number of chromosomal and other birth abnormalities in a developing fetus. These include: Down syndrome. Neural tube defects, such as spina bifida.

Does amniocentesis give false positives?

Interestingly, a false positive rate was reported to be 3.6% for early amniocentesis and 8% for mid-trimester amniocentesis.

How long should you rest after amniocentesis?

You may be told to rest on your left side. After the test, rest at home and avoid strenuous activities for at least 24 hours, or as directed by your healthcare provider.

How bad does amniocentesis hurt?

Is amniocentesis painful? Amniocentesis is not usually painful, but you may feel uncomfortable during the procedure. Some women describe experiencing a pain similar to period pain or feeling pressure when the needle is taken out.

How common is miscarriage after amniocentesis?

Statistics defining the risk of miscarriage following an amniocentesis vary considerably, but in general a miscarriage is thought to occur in 0.2 to 0.3% of amniocentesis procedures. This translates to a risk of miscarriage in between 1 in 300 and 1 in 500 pregnancies.

What is the advantage of chorionic villus sampling over amniocentesis?

The main advantage of CVS over amniocentesis is that it is performed much earlier in pregnancy, at 10 to 13 weeks, rather than 15 to 20 weeks. A disadvantage is that neural tube defects, such as spina bifida, can’t be detected.

Which is better amniocentesis or CVS?

For example, CVS is generally done earlier in pregnancy than amniocentesis and is particularly advantageous for detecting certain genetic conditions. Another important factor is the risk for miscarriage, which has been attributed to 0.5%-1.0% of CVS procedures and 0.25%-0.50% of amniocentesis procedures.

Which is more painful CVS or amnio?

Conclusion: In general, each procedure is associated with a tolerable amount of pain. TA-CVS appears to be the most painful procedure while TC-CVS appears to be the least painful procedure. In certain groups of patients, the procedures may be associated with higher levels of pain and/or anxiety.

Can amnio results be wrong?

Amniocentesis is estimated to give a definitive result in 98 to 99 out of every 100 women having the test. But it cannot test for every condition and, in a small number of cases, it’s not possible to get a conclusive result.