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Prenatal Genetic Screening

The BC Prenatal Genetic Screening Program oversees prenatal screening for Down syndrome, trisomy 18, and open neural tube defects across the province.
We ensure there is a centralized, coordinated system to guide prenatal genetic screening across the province, measure outcomes, evaluate and disseminate new evidence/knowledge, and provide educational and informational materials to women and health care providers. We have also improved prenatal screening by introducing newer screens with increased detection rates and fewer false positive rates. 

This section provides resources to assist health care providers in offering genetic screening in their medical practice. To navigate through this section, use the menu on the right (you can expand (+) or collapse (-) the menu as needed. 

Key Documents
Current recommendations for screening and answers to frequently asked questions can also be found in:

NIPT Funding

NIPT is funded for women who meet one of the following criteria:

  1. has received a Positive Screen result from IPS, SIPS, or Quad; 
  2. has had a previous trisomy 13, 18, or 21 pregnancy; or
  3. has a risk of Down syndrome greater than one in 300 based on results of screening and ultrasound marker(s) of aneuploidy. 
For more information, please visit our NIPT page.

Practice Changes

Prenatal Diagnostic Testing on Amnios and CVS at BCW and RCH

Rapid aneuploidy detection (RAD) will be used as the first tier prenatal diagnostic test for all patients at BC Women's Hospital and Royal Columbian Hospital. Conventional cytogenetic karyotype analysis will be performed only when indicated. 

Review the Information Sheet for Ordering Physicians

There are no changes to cytogenetic test ordering at Victoria General Hospital.

Handling of Amniotic Fluid Samples at RCH

Effective March 31, 2016, the Molecular Cytogenetic Laboratory at Royal Columbian Hospital will discontinue chromosome analysis on amniotic fluid samples procured from women who are at low risk (i.e. AMA). This change complies with the SOGC-CCMG guidelines from 2011 (J Obstet Gynaecol Can 2011;33(9):955–960) and standardizes testing between RCH and C&W Cytogenetic/Molecular Laboratory. 

All amniotic fluid samples sent to RCH Molecular Cytogenetic Laboratory will have Rapid Aneuploidy Testing (RAD) in the form of Fluorescence in situ Hybridization (FISH). In 99% of cases, that result will be available within one business day. The FISH RAD testing done at RCH will rule out trisomy 13, 18, and 21 and sex chromosome aneuploidy. If the FISH testing is normal, then the sample will not be further studied. If the FISH test is abnormal or inconclusive, then the sample will be cultured, and standard chromosome analysis will be performed and that result reported out. Please send the routine two tubes of amniotic fluid (10 mL fluid/tube).

Standard chromosome analysis will continue to be performed if there is a parental history of a cytogenetically visible chromosomal anomaly or a history of a previous child with a chromosomally visible abnormality.

Pregnant women who are at high risk (i.e. ultrasound abnormality) and potentially will require microarray analysis should have the amniotic fluid sample sent to the C&W Cytogenetic/Molecular Laboratory for RAD and microarray testing.

SOURCE: Prenatal Genetic Screening ( )
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