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Posts for tag: Genetic Testing

By Dr. Stephanie Lee
January 31, 2020
Category: OBGYN
Tags: Genetic Testing  

Finding out you’re pregnant is one of the most exciting moments for soon-to-be-parents. Throughout the course of your pregnancy you will want to have an OBGYN that you trust to guide you through the process and to provide you with the care and treatment you need to ensure a healthy pregnancy for both you and the baby. You will most likely be offered prenatal genetic testing during the first or second trimester of your pregnancy. If so, it’s important to understand more about genetic testing and why it’s done.

What is prenatal genetic testing?

These genetic tests are conducted during pregnancy to screen for certain birth defects and other fetal conditions. It is recommended that all pregnant women go through certain prenatal genetic testing, regardless of age or other risk factors. Of course, your obstetrician may recommend additional genetic testing if there are certain risk factors present.

What are the different kinds of prenatal genetic tests?

Here are the prenatal genetic tests that your OBGYN may offer or recommend:

First Trimester Screening

This screening involves both an ultrasound and blood test to check for certain birth defects including trisomy 18 (Edward’s syndrome), trisomy 13, neural tube defects and Down syndrome (trisomy 21). Even though these abnormalities increase with the mother’s age, it’s recommended that every pregnant women get this testing. This is usually the first set of prenatal genetic testing you’ll receive after you find out you’re pregnant.

Chorionic Villus Sampling

Chorionic Villus Sampling (CVS) is a prenatal test that detects genetic disorders, birth defects and other problems that may occur early on in the pregnancy. This procedure is usually performed within the first 10-12 weeks of a woman’s pregnancy at your OBGYN’s office. This testing can be performed as either a transabdominal CVS or transcervical CVS.

Amniocentesis

Amniocentesis allows your obstetrician to collect amniotic fluid, which can provide important insight into the health of your baby. Amniocentesis can check for fetal infections, can test your baby’s lungs, and check for genetic disorders such as Down syndrome. If amniocentesis is being performed for strictly genetic purposes then this is often performed between 15 to 20 weeks.

There are many reasons a woman or couple may choose to get genetic amniocentesis including advanced maternal age, positive results on other prenatal screenings or unusual ultrasound findings.

Cystic Fibrosis Carrier Screening

Cystic fibrosis (CF) is one of the most common and dangerous genetic disorders. Since cystic fibrosis is inherited a simple blood test can be performed to see if you are a carrier for CF. Testing positive on the carrier test does not necessarily mean that you will have a child with CF.

AFP + Screening

Alpha-fetoprotein (AFP) is a blood test that checks the levels of AFP (a protein produced by the baby’s liver) for signs of a birth defect, Down syndrome or neural tube defects. This test is usually offered between 15 and 20 weeks and is most often recommended in pregnant women over 35, as well as women with diabetes.

Your OBGYN is here to make sure that all of your questions and concerns about you and your baby’s health are addressed during your pregnancy, so if you have any questions about genetic testing your doctor would be happy to sit down with you and discuss these testing options.