RCSI Women's Health

What tests are available for me to figure out if my baby is healthy?

Information about First Trimester Screening (FTS)

The vast majority of babies are normal. However all women, whatever their age, have a small risk of delivering a baby with a physical or a mental problem. In some cases this may be due to chromosomal problems such as Down syndrome. Further information on fetal chromosomal problems is available by clicking here.

The only way to know for sure whether or not your baby may have a chromosomal problem is by having an invasive test, such as Chorionic Villus Sampling (CVS) or amniocentesis (amnio). However, these tests have a small chance of causing a miscarriage of about 0.5% to 1% (about one chance in 100 or one chance in 200).

This FTS test helps you and your partner decide whether the chances that your baby may have a chromosomal problem is high enough to warrant having an invasive test, such as CVS or amnio.

(* Unable to play the video? - see bottom of the page)

  The most accurate way of estimating the chances of your baby having a chromosomal problem is the FTS test, which is carried out at 11-13 weeks, and includes:
  • Your age
  • Nuchal Translucency (amount of fluid behind the neck of the fetus on ultrasound)
  • Presence or absence of any physical abnormalities on ultrasound
  • Level of two proteins (F-hCG & PAPP-A) in your blood.

By combining this information, the FTS test can identify about 9 out of 10 pregnancies (90%) in which the baby has Down syndrome. This is more accurate than either the ultrasound part or the blood part of the test done on their own. First trimester screening using the nuchal scan on its own, without also performing the blood test portion, has been proven to be an inferior test, with higher false positives, and lower detection.

Since the blood test for the protein levels is done in our unit, your results will be available immediately. The chances of Down syndrome will then be discussed with you. Only you can decide if you wish to have an invasive diagnostic test based on this risk.

If the thickness of the back of the babys neck is quite big other problems may be present.  These are very rare but include heart problems.

This special FTS scan also provides other very useful information:

  • Accurate dating of the pregnancy
  • Fetal heart rate
  • Number of fetuses present and, if twins, whether they are identical or not
  • Detects obvious fetal abnormalities
(* Unable to play the video? - see bottom of the page)
It is important to remember that a screening test does not guarantee a normal baby. Therefore you should carefully compare the advantages and disadvantages of a screening test (like FTS) compared with a diagnostic test (like CVS).

Only you can decide if you wish to have an invasive diagnostic test, like CVS, and you will always have the right to choose this definitive test if you prefer. It is also recommended that you have a further scan at 20 weeks to check the baby so that we can reassure you about problems that the CVS cannot detect.

To make a First Trimester Screening appointment please call (01) 878 6070.

  Patient Information Brochure (Print Friendly Version)

Early Pregnancy Assessment
First Trimester Screening
Second Trimester Screening
Fetal Anomaly Scan
Chorionic Villus Sampling

If the video doesn't play when you click on the link you may need additional software.
Please select from the list below:

Windows XP/2000
DivX codec v6.2.5 for Windows XP/2000 (14.3MB)
Windows ME/98
DivX codec v5.2.1 for Windows ME/98 (7.3MB)
Mac OS X
DivX codec v6.5.0 for Mac OS X (12.0MB)
Mac OS
DivX codec v5.1.1 for Mac OS (2.1MB)

RCSI Women's Health Homepage

Contact Details
© 2006 Royal College of Surgeons in Ireland and Others