About the Nuchal Translucency Quality Assurance (NTQA) program

The Nuchal Translucency Quality Assurance (NTQA) program defines the requirements for NT registration in Ontario and provides the tools for supporting sonographers performing NT measurements for Multiple Marker Screening.

Role of NT in Multiple Marker Screening (MMS)

The fetal nuchal translucency (NT) is a collection of fluid that is present at the back of the fetal neck in the first trimester of pregnancy. An increased NT measurement can be a normal variant, but is associated with a higher chance for chromosome differences, cardiac defects and other conditions.

A sonographer or physician measures the thickness of the fetal NT when the fetal crown rump length (CRL) is between 45mm and 84mm (approximately 11 ̶ 14 weeks gestation). If the pregnant individual is having enhanced First Trimester Screening (eFTS) or screening for vanishing twins/co-twin demise, this NT measurement is submitted to one of the three Ontario MMS laboratories along with a blood sample. The laboratories use this measurement along with clinical information and biochemical serum markers to calculate the individual chance for a pregnancy to have trisomy 21 (Down Syndrome) or trisomy 18. The NT measurement is the most heavily weighted factor in this equation.

Visit the Fetal Medicine Foundation (FMF UK) website for more information about the fetal NT, the relationship between the NT measurement and prenatal screening, and the diagnostic requirements of NT ultrasound.

Importance of a NTQA Program 

Since the incorporation of the NT measurement into the prenatal screening process, sonographers have played a significant role in providing excellent quality risk assessment for trisomy 21 (Down syndrome) and trisomy 18.

Registration with the NTQA program has many benefits. It will allow you, as a sonographer or physician, to perform nuchal translucency (NT) measurements for Multiple Marker Screening tests, such as enhanced First Trimester Screening (eFTS). It will also allow you compare your NT measurement performance against international standards and obtain support to improve or maintain the quality of your scanning.

Your other team members

Physicians who report but do not scan NT ultrasounds, do not require an Ontario NT ID number. PSO recommends that these physicians complete the Fetal Medicine Foundation (FMF) 11-13 weeks scan course to refresh their knowledge on proper NT measurement protocol. They should also ensure that sonographers are complying with the expectations of Ontario's NTQA program.

Quality advisors or medical directors who oversee sonographers performing NTs are recommended to sign up to receive communications regarding Ontario's NTQA program.