NIPT via the National Genomics Test Directory

The NHS is offering NIPT testing for women with a confirmed previous affected pregnancy with any full trisomy for chromosome 21, 18 or 13 via the National Genomic Test Directory under referral code R445.

This is not part of the NHS FASP Screening Pathway although HSL are providing this testing to hospitals in the same region as for FASP.

Inclusion criteria

• All women with history of pregnancy with a full trisomy of T21, T18 or T13 should be offered NIPT in any subsequent pregnancy.
• R445 is offered from 10+0 to 21+6 weeks inclusive, confirmed by ultrasound scan (USS), to both singleton and twin pregnancies.
• Eligibility for R445 should be established prior to offering the test. See the R445 test entry within the NGTD for latest eligibility and exclusion criteria.
• It is recommended that the report from the previous affected pregnancy is reviewed to confirm full trisomy of T21, T18 or T13 prior to offering R445. However, R445 can still be offered even if the previous report is unavailable or obtaining it will cause a delay in screening. In such cases it should be explained to the woman that R445 is being performed on the basis that the previous pregnancy was a full trisomy T21, T18 or T13 and not another chromosomal anomaly, as these will not be detectable by NIPT

Exclusions  

• Existing NHS FASP exclusions: vanished twin pregnancy, current maternal cancer, balanced translocation (T21, 18, 13), maternal T21, bone marrow/organ transplant, blood transfusion in the last 4 months.
• Previous pregnancy was a trisomy involving chromosomes other than T21, T18 or T13. - Previous pregnancy was not a full trisomy: e.g., mosaicism, translocation or, partial trisomy of T21, T18 or T13. – One of the parents has a Robertsonian translocation or balanced translocation involving chromosome T21, T18 or T13. – Donor egg used in current pregnancy. In these cases, referral to genetic counselling and / or fetal medicine should be offered.
• For full details refer to the National Genomic Test Directory https://www.england.nhs.uk/wp-content/uploads/2018/08/Rare-and-inherited-disease-eligibility-criteria-version-6-January-2024.pdf

Ordering a test

Please ensure the eligibility for R445 NIPT is confirmed by ticking the box to identify the trisomy the previous pregnancy was affected with on the R445 Request Form, see below.

Click here to download the HSL NHS Test Directory R445 Referral Form

Use the NHS FASP sample collection packs replacing the FASP request form with the R445 request from. The rest of the process remains the same as for FASP NIPT requests.

Screening pathway guidance for healthcare professionals can be found using the link below:

Click here to download NHS R445 Screening pathway and guidance for healthcare professionals

Please refer to this document for information regarding the implementation of this pathway. If you have any questions for the laboratory please contact us the NHS FASP email address: nhsfasp@hslpathology.com