Maternal Screening Testing
Helping You Understand the Risk of Birth Defects
Would you want to take a simple test to let you know if you have a higher than average chance of having a baby with
certain birth defects? If you were told you had an increased risk, would you want further testing to tell for sure?
If the answer to these questions is “Yes,” we can help.
First Trimester Screening
First Trimester Screening is done by combining a blood test with a specific ultrasound measurement during the 1st
trimester of the pregnancy. By combining information from these tests, pregnant women can learn how high the chance
is that the fetus has Down syndrome or a different chromosome problem called Trisomy 18. If a woman's chance s
of having a baby with one of these problems is high enough, she could choose to have a follow-up test to know for
sure.
Download an informational brochure on First Trimester Screening
Second Trimester AFP+ (Quad) Screening
AFP+ screening measures the levels of certain substances (alpha-fetoprotein or AFP, unconjugated estriol, human
chorionic gonadotropin, and Inhibin-A) in a pregnant woman’s blood. These substances come from the fetus and
placenta and are found in the blood of all pregnant women. It is normal for the levels of these substances to vary
among different women, but some women with particularly high or low values may be at increased risk for having a
baby with certain birth defects.
AFP+ test is called a “screening” test because it cannot tell for certain whether the fetus does or does
not have a birth defect. It can identify women who have a greater than average risk for having a baby with certain
birth defects. These women may then choose to have other tests (such as ultrasound or amniocentesis) that can help
tell with greater certainty if a birth defect is present. About 7 out of every 100 women who have AFP+ testing will
need some further testing, but most of the time those women will deliver a normal, healthy baby.
Download an informational brochure on Second Trimester AFP+ (Quad) Screening
Is this Testing Right for You?
If you would like to have maternal screening done during your pregnancy, talk to your doctor or call Reproductive
Genetics at (585) 275-3304.