All pregnant women are now being offered Nuchal Translucency (NT) and First Screen for certain birth defects. It is important that you understand this screening process so that you can decide whether or not to be tested.

What is First Trimester Screen with NT?
First Trimester Screen with NT is a test that can help determine your risk for having a baby with Down syndrome, Neural Tube defects, trisomy 13 or trisomy 18. The test is done between 11 & 13 weeks gestation and includes both an ultrasound and a blood test. If patients are interested, Cystic Fibrosis Carrier Testing can be included in your First Trimester Screen test (see handout on Cystic Fibrosis for more information). The blood test is done by taking a small sample of blood from your fingertip. The blood is placed on a special testing card and sent out for examination. The NT ultrasound is performed by a credentialed specialist who will measure the amount of fluid in the back of your baby's neck (this is the nuchal translucency). It is normal for all developing babies to have some fluid at the back of the neck, but larger amounts of fluid may indicate in increased risk. First Trimester Screen and NT testing must be done together, as NT ultrasound alone is not an adequate evaluation of your risk.

What does it mean if my screen is negative?
A negative First Screen and NT result means that the likelihood of your baby having the birth defects listed above is reduced. However, a negative screen does not guarantee that the baby will be normal, because maternal serum screening does not identify all unborn babies with these problems. Nor will it diagnose other birth defects a baby may have.

What does it mean if my screen is positive?
If your screen is positive, it means that your unborn baby is at increased risk for a problem. It does not mean that your baby has a birth defect. The vast majority of women with "screen positive" results do not have babies with genetic defects. However, if your screen is positive, you may want to consider other tests such as: additional ultrasound, repeat blood tests, or amniocentesis. Follow up options are determined privately between a woman and her doctor.

Whether or not you have more testing is up to you. Remember the First Screen and NT test is not a diagnostic test. It will not tell you whether or not your unborn baby has or doesn't have a problem. It will simply indicate the chance the baby has a problem.

Who might decide NOT to have a screening?
Knowing about these problems ahead of time may change the management of your pregnancy and your delivery. However, some women decide that they do not want to know during the pregnancy if their baby has one of these problems. If this is your decision, you should not have your blood drawn.