by Anna Hicks
Pregnancy is a joyous time, and all that any mother wants is to give birth to a healthy and happy little boy or girl with as few complications as possible, or hopefully none at all.
In recent years, testing for certain conditions has come a long way, and now we can find out a wealth of information about your baby before it ever leaves your body. These tests might have once been considered purely science fiction, but with breakthroughs in the science and technology surrounding genetics, they’re quickly becoming commonplace for mothers with risk factors that include advanced age, or familial history with certain types of conditions.
DNA screening is on almost every expecting mother’s mind, and with good reason. But what is it? What should you know about it before asking your healthcare professional to order the test? It’s important you gather as much information regarding to prenatal DNA testing before making any big decisions.
Who Should Get Tested?
Your healthcare provider will be able to answer this question conclusively, but those that have a family history of Trisomy 21, Trisomy 18, or Trisomy 13, as well as mothers with advanced age (35 years and older), a positive serum screen, and an ultrasound finding are the most common candidates for testing. That said, your healthcare provider could order the test for a wide range of other conditions or as a precautionary measure.
How Does it Work?
Your healthcare professional will take a small amount of blood and send it to a lab. The sample is then tested for the presence of multiple genetic defects (more on this later) as well as fetal gender. The lab results are typically available to view in your physician’s office in as few as five days from the date the lab received the initial sample.
What Does it Screen For?
The test screens for the presence of the three most common genetic conditions, Trisomy 21 (Down syndrome), Trisomy 18 (Edwards syndrome) and Trisomy 13 (Patau syndrome). Most people have 23 pairs of chromosomes, with each responsible for carrying thousands of genes. The first 22 pairs are called autosomes and the final set of chromosomes, the 23rd pair, are the sex chromosomes (xy for female, xx for male). Some are born with a pair of duplicated chromosomes, which are known as trisomies. These trisomies are what the test is looking for.
How Common Are These Conditions?
Trisomy 21 occurs in approximately 1 in every 830 births, making it the most common of the trisomies. Trisomy 18 appears in 1 in every 5,000 births, and Trisomy 13 is decidedly more rare, appearing in 1 of every 16,000 births.
Is This a Replacement for Amniocentesis?
No. This test is not an alternative for the traditional amniocentesis, and your doctor may still order one depending on the results of the test. This is simply a non-invasive prenatal test that often alerts the healthcare professional of the presence of these trisomies without the risks of prenatal invasive procedures.
As you can see, prenatal testing has certainly come a long way. The future is even more exciting as the technology begins to catch up with the science behind genetic testing and new discoveries are made that allow expectant parents to know even more about their children before they’re ever born. It’s an exciting time to be alive, isn’t it?