Prenatal Testing

Prenatal testing can provide valuable information about your baby's health. These tests are optional, but if you are considering any, it is important you make informed decisions.

Here are some questions to consider and discuss at length:
  • What do the test results determine or diagnose?
  • How accurate are the results?
  • How will the information affect my prenatal care?
  • What are my risks?

There are many ways to help ensure a safe pregnancy and delivery of a healthy baby. Besides practicing good health and nutrition habits, you can speak with your doctor about prenatal testing. These tests range from commonly used techniques like ultrasound to advanced screening for those whose babies may have a high risk of birth defects. 

There are several common forms of prenatal testing:
  • Chorionic Villus Sampling - In this test, a small sample of cells is taken from the placenta, either through a catheter or a needle. Your doctor can determine from these cells whether there are any potential defects in chromosomes. Chorionic villus sampling is normally performed in the first trimester of pregnancy.
  • Maternal Serum Alpha-Fetoprotein (MSAFP) Testing - The MSAFP test is a blood test that helps identify pregnant women who have high blood levels of alpha-fetoprotein, which carries an increased risk of a baby being born with an open neural tube defect (like spina bifida). This test can also diagnose chromosomal defects that contribute to conditions such as Down syndrome or trisomy 18 (also known as Edwards syndrome). This test only assesses the potential for problems and cannot provide a definitive diagnosis.
  • Amniocentesis - Amniocentesis involves taking a sample of amniotic fluid — the fluid that surrounds your baby during pregnancy — with a needle carefully inserted into the uterus through your abdomen. Amniocentesis is used to check for chromosomal defects, as well as other potential conditions.
  • Ultrasound - Ultrasound is one of the most commonly used procedures in prenatal screening and routine prenatal care. Using high-frequency sound waves to create images of internal organs, ultrasound imaging is safe and useful for assessing the development of your baby. Your doctor uses these images to address any concerns and give you a first look at your little one.

We are always available to answer any questions you might have about prenatal testing. For more information, just ask your doctor.


Our physicians at Houston Methodist specialize in prenatal testing at the following convenient locations: