Our Outpatient Services

Amniocentesis

What is an amniocentesis?

An amniocentesis or “amnio” is a diagnostic procedure that samples the amniotic fluid surrounding the developing fetus.  Within this fluid (which happens to be fetal urine) are fetal cells that have been shed from the fetal skin, genitourinary system and lungs that can be tested to determine the presence or absence of a chromosome abnormality.

What is the difference between a screening and diagnostic test

Unlike the California prenatal screening program which provides a result that identifies the odds a pregnancy will be affected with an abnormality, a diagnostic test such as an amniocentesis will  provide an answer – with nearly 100 percent accuracy – whether the pregnancy is affected with a chromosome disorder or not.

Which tests can be performed on an amniocentesis sample?

Most commonly, an amniocentesis sample is used to test for chromosome abnormalities such as trisomy 21 (Down syndrome), trisomy 13, trisomy 18 (Edwards syndrome), sex chromosome abnormalities and in some cases, specific genetic disorders such as cystic fibrosis, fragile X or sickle cell disease.

How is an amniocentesis performed?

Using ultrasound guidance, a very fine needle is guided through the lower abdomen into the amniotic fluid.  A small sample of fluid is withdrawn and sent for chromosome/genetic testing.  The fetus is kept in view at all times to assure the procedure is accomplished safely.  Despite most women’s fears that the procedure is painful, in our experience approximately 97 percent of our patients report the procedure to be significantly less painful than they expected.

What are the risks of an amniocentesis?

The risk of miscarriage following an amniocentesis is less than 1 in 1,000.  Our specialized center with qualified, experienced board certified perinatologists and state-of-the-art equipment minimizes the risks associated with amniocentesis.

I wouldn’t terminate my pregnancy regardless, so why would I do an amniocentesis?

Pregnancies affected with Down syndrome are managed very differently than those that are not.  Performing an amniocentesis may improve the outcome of your pregnancy, provide peace of mind or help you prepare for the delivery of your baby.

Who should consider an amniocentesis?

Women who are:  35 years or older, have a prior pregnancy affected with a chromosome disorder,  have a family history or are at risk for a specific genetic disorder or have received abnormal results from an early screening test (first trimester screening).

 

 

Who should consider an amniocentesis?

You should consider an amniocentesis if:

  • You are 35 years of old or older
  • You have had a chromosome abnormality in a previous pregnancy
  • You have a family history or are at risk for a specific genetic disorder
  • You have received abnormal results from a screening test