Original Title: Détermination du sexe fœtal par analyse de l’ADN circulant en cas de risque génétique: rapatriement d’une analyse réalisée hors Québec

Authors' objectives: At the MSSS's request, the Institut national d'excellence en santé et en services sociaux (INESSS) is reviewing the current state of knowledge and the optimal implementation of these NGS analyses within the Quebec healthcare system. This report specifically addresses an analysis designed to determine fetal sex based on circulating cell-free DNA in cases of pregnancies at risk of sex-linked genetic diseases in the fetus.

Authors' results and conclusions: RESULTS (#1 FETAL SEX DETERMINATION ANALYSIS-CURRENT CARE AND SERVICES PATHWAY): When the fetus is at risk of developing a severe sex-linked genetic disease, pregnancy monitoring is carried out in referral centres specialized in fetal-maternal medicine and medical genetics (#1.1 FETAL SEX DETERMINATION ANALYSIS-CLINICAL VALIDITY): According to the literature review, the performance of fetal sex determination tests using cell-free circulating DNA is high, with sensitivity and specificity values exceeding 95% when samples are taken from 10 weeks of pregnancy onwards. (1.2 FETAL SEX DETERMINATION ANALYSIS-CLINICAL UTILITY): Fetal sex determination could also be used to plan the delivery of male fetuses at risk of hemophilia and to inform the need to initiate or continue maternal steroid treatment to reduce virilization of the external genitalia in female fetuses at risk of developing CAH. (#2 ORGANIZATIONAL CONSIDERATIONS-CURRENT SERVICE OFFER): Logistical constraints associated with sending samples to France can have an impact on sampling and may delay the reception of results. (#2.1 ORGANIZATIONAL CONSIDERATIONS-REPATRIATION STRATEGY): Samples intended for fetal sex determination can follow the same trajectory as those assigned to the non-invasive prenatal test (NIPT), thus avoiding the development and validation of a new method. (#2.2 ORGANIZATIONAL CONSIDERATIONS-RESPONSE TIME): According to the clinicians consulted, the proposed response time of 7 to 10 business days is appropriate and aligns well with the standard schedule for invasive diagnostic tests. (#2.3 ORGANIZATIONAL CONSIDERATIONS-VOLUMETRY): Over the next three years, the requesting laboratory anticipates approximately 50 analyses per year. Data show that a stable number of analyses has been performed outside the province of Quebec (between 20 and 40 per year). (#2.4 ORGANIZATIONAL CONSIDERATIONS-IMPACT ON RESOURCES AND THE ORGANIZATION OF CARE AND SERVICES): Improved response times and reduced logistical constraints related to shipments outside Quebec are anticipated following repatriation. (#3 SOCIOCULTURAL CONSIDERATIONS): Health authorities, regulatory agencies, and learned societies recommend the use of a non-invasive test for fetal sex determination when there is a medical justification, such as a risk of X-linked disease or CAH. (#4 ECONOMIC DIMENSION): A budget impact analysis indicates that repatriating the test could generate savings of approximately $8,700 ($5,800 to $15,600) over the first three years by avoiding the costs associated with shipping samples outside Quebec. CONCLUSION: This state of knowledge summary aims to support the MSSS in the process of repatriating a test for fetal sex determination using circulating cell-free DNA sequencing. This test, currently performed outside the province of Quebec, is indicated for pregnant women whose fetuses are at risk of severe sex-linked genetic diseases. As part of this exercise, no major concerns were identified that could hinder the optimal deployment of this analysis in Quebec.

Project Status: Completed

URL for project: https://www.inesss.qc.ca/publications/repertoire-des-publications/publication/determination-du-sexe-foetal-par-analyse-de-ladn-circulant-en-cas-de-risque-genetique.html

Year Published: 2025

URL for published report: https://www.inesss.qc.ca/publications/repertoire-des-publications/publication/determination-du-sexe-foetal-par-analyse-de-ladn-circulant-en-cas-de-risque-genetique.html

English language abstract: An English language summary is available

Publication Type: Other

Country: Canada

Province: Quebec

Organisation Name: Institut national d'excellence en sante et en services sociaux

Contact Address: L'Institut national d'excellence en sante et en services sociaux (INESSS) , 2021, avenue Union, bureau 10.083, Montreal, Quebec, Canada, H3A 2S9;Tel: 1+514-873-2563, Fax: 1+514-873-1369

Contact Name: demande@inesss.qc.ca

Contact Email: demande@inesss.qc.ca

Copyright: L'Institut national d'excellence en sante et en services sociaux (INESSS)