FAQ

First Trimester Combined Screening (FTS)

What is the First Trimester Combined Screen (FTS)?

FTS is a prenatal screen for chromosome conditions and early identifiable birth defects. FTS involves:

• A maternal blood test performed between 8 – 13 6/7 weeks to measure PAPP-A and free B-hCG.
• An ultrasound performed between 11 – 13 6/7 weeks to measure the fetal nuchal translucency*

These results, combined with a woman’s age are used to predict a woman’s chance of having a baby with Trisomy 21, Trisomy 13 or Trisomy 18. The ultrasound is also used to screen for early detectable birth defects. The detection rate for chromosome conditions is 85-90%

All nuchal translucency ultrasounds of the FTS Program must be performed at EFW Radiology, Specialists in Diagnostic Imaging.

Is Screening for chromosome conditions recommended for all pregnant women?

Yes. It is consistent with the current Canadian Guidelines on Prenatal Screening.

What are the advantages of the FTS screen over other screens currently available?

1. Screening at an early gestational age:

Women want to make informed choices on information that is complete and available as early as possible in their pregnancy.

2. Screen accuracy:

3. Fewer diagnostic procedures:

As a result of the improved accuracy, it is expected that fewer women with unaffected pregnancies will undergo invasive prenatal diagnosis leading to a reduced number of procedure-related pregnancy losses and improved perinatal outcomes.

What about 15-19 6/7 weeks Maternal Serum Screening (MSS)?

Currently, we advise that a woman undergo only ONE Down syndrome screen per pregnancy.

• If a patient presents after 14 weeks or has not had the FTS, she can be offered MSS at 15-19 6/7 weeks.
• If a patient has had FTS, then MSS can be offered for neural tube defect screening only. However the recommended 18 week ultrasound is highly accurate for detecting for major birth defects including the majority of serious neural tube defects.

Please Note – If you wish your patient to have FTS, do not complete a MSS requisition and send blood to the CLS laboratory. An appointment for FTS is required.

What about multiple gestations?

Currently, patients with a confirmed multiple gestation would be eligible for NT screening alone.

What type of results will be provided to my patient?

Women receive a personalized first-trimester risk estimate for Trisomy 21, Trisomy 13 and Trisomy 18. This is called the ‘adjusted risk’ in the FTS report.

Prenatal testing and obstetric management options that are relevant to the patient and her FTS result are then discussed at the clinic appointment or by phone. Guidelines used when counselling are as follows:

Women with a previous affected pregnancy and women > 35 years are offered prenatal diagnosis regardless of results.

Guidelines used when counselling:

What do I inform my patients about their FTS appointment?

When informing your patients about their appointment please advice them that:

• This is a screening test that involves a blood test and ultrasound.   
• A full bladder is not required. Women will be asked to drink water when they arrive.

Contact numbers: Appointments: 289-9269. Program Manager: 943-8382. Program Secretary: 932-8379.

How do I find patient and care provider information?

• A patient education video and FTS patient brochure is available online or through the Program.
• ‘House Calls’. Members of ERA Program are available to offer an in-service at your clinic at a time convenient to you and your staff. Contact the Program Manager to make arrangements.