Assessment of an increased risk of inherited disease should be available to all individuals considering a pregnancy. Genetic counselling for possible carrier screening should be offered to individuals identified as being at elevated risk of transmission of an inherited condition based on family history, ethnic background, or past medical/obstetrical history. When the a priori risk is elevated, carrier testing may be offered. Expanded carrier testing using large panels yields few carrier pairs (at most 1% even with larger panels) and therefore is not recommended as a routine test at this time. Additionally, the utilization of limited laboratory, clinical and genetic counselling resources requires stewardship. Since the evidence is limited, routine carrier screening of all individuals is not recommended at this time. However, this may be revisited if evidence of effectiveness and efficiency is established and implementation strategies are proposed.
Sources:
Hussein N, et al. Preconception risk assessment for thalassaemia, sickle cell disease, cystic fibrosis and Tay-Sachs disease. Cochrane Database Syst Rev. 2021 Oct 11;10(10):CD010849. PMID: 34634131.
Peyser A, et al. Comparing ethnicity-based and expanded carrier screening methods at a single fertility center reveals significant differences in carrier rates and carrier couple rates. Genet Med. 2019 Jun;21(6):1400-1406. PMID: 30327537.
Wilson RD et al. Joint SOGC-CCMG Opinion for Reproductive Genetic Carrier Screening: An Update for All Canadian Providers of Maternity and Reproductive Healthcare in the Era of Direct-to-Consumer Testing. J Obstet Gynaecol Can. 2016 Aug;38(8):742-762.e3. PMID: 27638987.