What is Prenatal Genetic Screening?
Genetic screening falls under the umbrella of prenatal genetic testing. Screening tests are used to screen for potential birth defects and provide expectant parents with more information about their pregnancy and the health of their baby. It is important to note that genetic screening is not the same thing as genetic testing. Screening calculates the odds of a child being born with an abnormality. Genetic testing can allow doctors to see chromosomal abnormalities and the conditions associated with these abnormalities. There are many screening tests available to pregnant women in NJ, including non-invasive prenatal testing for Down syndrome.
What are the Odds of my Child Being Born with a Genetic Disorder?
The odds of a child having a genetic disorder come from a variety of sources. The genetic screening test is viewed along with a myriad of other factors. Family genetic history and the mother’s age are even put into account when calculating these odds. 1 out of every 33 children is born with some kind of birth defect, so it is more common than many parents think. Testing for conditions like Down syndrome or sickle cell anemia can be important in how the rest of the pregnancy is approached. Certain conditions can force an expectant mother to modify her diet or activity levels.
What are the Different Types of Prenatal Genetic Screening Tests?
Prenatal genetic screening includes different types of tests to determine the risk of your baby being born with certain disorders. The tests evaluate the different substances in a mother’s blood that are usually linked to genetic disorders. Carrier screening tests are available for prospective parents and involve a blood or tissue sample from the inside of the cheek. This type of test can be done before or during pregnancy and can be used to scan for the presence of genes for certain inherited disorders. Prenatal genetic screening tests can also be performed via a pregnant woman’s blood or ultrasound findings. This is what first-trimester and second-trimester screenings refer to. These types of tests can include:
- Nuchal translucency screening to check for the risk of Down syndrome
- Blood tests to screen for Down syndrome, Edwards syndrome, and neural tube defects (NTDs)
- Ultrasounds to check for physical defects of the brain, spine, facial features, abdomen, heart, and limbs
When is the Best Time for Prenatal Genetic Screening?
The best time for prenatal genetic screening depends on the type of testing you receive. The first-trimester test is usually done between the 10th and 13th weeks of pregnancy. Tests can also be done in the second trimester. For example, an ultrasound to check for physical defects would normally be performed between 18 and 22 weeks of pregnancy. If screening tests indicate an increased risk for a certain disorder or condition, diagnostic tests may be ordered to confirm the diagnosis. Diagnostic tests can include chorionic villus sampling or amniocentesis.