Produced by the Centre for Genetics Education.
Important points
• There are a number of different prenatal tests and procedures available to assess the development of the baby. Each has advantages, disadvantages and limitations
• There is no test that gives a 100% guarantee of a healthy baby. The tests give some information about the baby’s health. They do not find all potential health problems
• Counselling before a test is done, will help the woman decide which test, if any, is best for the woman and the baby
• Each prenatal test is done at a certain time during the pregnancy starting at 8-10 weeks and going through to 20 weeks and include:
– Prenatal screening tests that may identify a baby as being at an increased risk of having a particular problem. All pregnant women, regardless of their age or family health history, may choose to have one of these prenatal screening tests that include ultrasound; early pregnancy (first trimester) screening: nuchal translucency ultrasound with or without testing of the mother’s blood; second trimester screening: testing of the mother’s blood (maternal serum testing)
– Prenatal diagnostic tests that are used to see if the baby actually has a particular problem. Even if the test result is normal, however, the baby could still have some other problem. Prenatal diagnostic tests include ultrasound; chorionic villus sampling (CVS); amniocentesis; cordocentesis
– Preimplantation genetic diagnosis (PGD) is used to test the embryo created via in vitro fertilisation (IVF) therapy prior to implantation