Guidance

Sickle cell and thalassaemia screening pathway requirements specification

Published 21 June 2021

Applies to England

This document provides an overview of sickle cell and thalassaemia (SCT) screening by describing what should happen at each stage of the pathway. It should be read alongside other guidance for the NHS SCT screening programme, including:

• screening standards
• programme handbook
• handbook for antenatal laboratories
• handbook for newborn laboratories

More detail on SCT screening in newborn babies is described in the newborn blood spot (NBS) screening pathway requirements.

Please also read the general information relevant to all the NHS screening programme pathways.

Sickle cell and thalassaemia screening

The NHS offers SCT screening to all pregnant women. If the mother is identified as a genetic carrier, screening is also offered to the baby’s biological father.

The programme screens for:

• sickle cell disease (SCD)
• thalassaemia
• other haemoglobin conditions

The purpose of the SCT screening programme is to identify women and couples who are ‘at risk’ of having a baby with a major haemoglobin disorder so they can be supported to make informed choices during the pregnancy.

SCT screening should be completed by 10 weeks gestation to allow time for any subsequent actions that may be required. Women and couples at risk of having a baby with SCD or thalassaemia must be offered prenatal diagnosis (PND) as early as possible, ideally by 12 weeks gestation.

The screening pathway varies slightly depending on if the hospital trust is in a high or low prevalence area for SCT.

Find out more about SCT screening in the programme overview.

End-to-end pathway

The SCT screening pathway consists of the following elements.

The dotted boxes and numbered labels show how the different parts of the pathway map to the generic headings used below.

An accessible text-only version of this pathway is also available.

1. Before screening test

These requirements relate to making sure screening is offered to the correct people.

Providers must have systems in place to:

• make sure there is a weekly failsafe in place to identify the eligible population
• make sure women receive verbal and digital information about SCT screening during first contact or booking visit with the midwife
• make sure women who are unable to access the digital version of Screening tests for you and your baby (STFYAYB) are given a physical copy
• make sure women are signposted to or given STFYAYB translations or STFYAYB easy guides as appropriate
• make sure women are given an opportunity to discuss their screening options with a well-informed healthcare professional
• establish whether the woman or couple is already aware of their screening status so known ‘at risk’ women or couples can be fast-tracked for timely PND
• establish whether the woman or couple has any special circumstances that may affect the screening pathway; refer to the SCT screening special circumstances care pathway for more information
• make sure women in low prevalence areas:
  • are offered the family origin questionnaire (FOQ) as an initial screening tool to determine if they are likely to be a carrier for SCD or other haemoglobin condition
  • are offered a screening blood test for haemoglobin variants if either parent is in a high risk group
  • are offered a screening blood test for thalassaemia (irrespective of family origins)
• make sure women in high prevalence areas are offered a screening blood test for SCD, thalassaemia and other haemoglobin disorders (irrespective of family origins)
• make sure all biological fathers (in high and low prevalence areas) are offered screening for SCD, thalassaemia and other haemoglobin variants if the woman is identified as a genetic carrier of a haemoglobinopathy
• maintain clear and accurate records of the woman’s decision (and the biological father’s decision, where applicable) in the woman’s maternity notes
• make the appropriate professionals, including laboratory staff, aware of women who decline screening
• make sure all women are tracked through from offer of screening to the end of the pathway
• make sure all newborn babies are offered sickle cell screening as part of the NBS screening programme
• encourage all healthcare professionals who offer SCT screening to complete the e-learning and study days, including:
  • the NHS screening programme e-learning modules
  • laboratory update days for bench level staff, haematology laboratory managers and consultant haematologists
  • haemoglobinopathy SCT screening programme update study days
  • haemoglobinopathy specialist counsellors update study days
  • the genetic risk assessment and counselling module for all health care professionals who provide counselling to ‘at risk’ couples identified by the SCT screening programme

Refer to the SCT programme handbook for additional details.

2. Screening test

These requirements relate to the processes of carrying out the screening test.

Coverage

Providers must have systems in place to return data for the coverage standard SCT-S01: antenatal screening (KPI ST1).

Carrying out the screening test

Providers must have systems in place to:

• make sure the correct screening test is offered depending on if the hospital trust is in a high or low prevalence area for SCT
• make sure the healthcare professional checks the woman’s (and the biological father’s, where applicable) understanding of the screening test and of the choices that will follow if the test is positive
• make sure an interpreter is available as required
• maintain clear and accurate records of the woman’s decision (and the biological father’s decision, where applicable) in the woman’s maternity notes
• perform the blood test and send it to the laboratory for testing along with a completed paper or electronic FOQ
• make sure women who did not attend their appointment(s) are followed up
• encourage all healthcare professionals who undertake SCT screening to complete the relevant education and training resources
• make sure there are weekly failsafes in place to check that samples taken are received in the laboratory with a completed FOQ and confirmed screen positive results have been communicated to antenatal screening team
• return data for:
  • test standard SCT-S02: timeliness of antenatal screening (KPI ST2)
  • test standard SCT-S03: completion of FOQ (KPI ST3)
  • test standard SCT-S04: turnaround time (antenatal screening)
  • test standard SCT-S07: timely reporting of PND results
  • test standard SCT-S08: reporting newborn screen positive results

Refer to the antenatal screening section of the SCT programme handbook and the handbook for antenatal laboratories and handbook for newborn laboratories for additional details.

Screening outcome and referral

Providers must have systems in place to:

• make sure SCT screening results are reported to the designated healthcare professional ≤ 3 working days following receipt of the blood sample in the laboratory
• make sure the father’s screening results are linked to the maternal results and followed up (where applicable)
• inform women (and the baby’s father, if applicable) of their screening results in line with local guidelines
• make sure there is a weekly failsafe in place to check all women and babies’ biological fathers who have accepted are tested
• advise women who have a screen negative result that their baby will be offered SCT screening as part of the NBS screening test; the antenatal SCT screening pathway ends for this group
• invite all women and couples with inconclusive results, who are carriers or who have a condition for a face-to-face counselling session and verbal confirmation of their screening result
• provide all women and couples with inconclusive results, who are carriers or who have a condition with the relevant information leaflet
• make sure the screening results are recorded in the woman’s:
  • handheld maternity records
  • electronic maternity record
  • primary care health record
• offer PND to all ‘at risk’ women and couples as soon as possible (ideally by 12⁺⁰ weeks gestation)
• initiate urgent referral for ‘at risk’ women and couples who decide to proceed with PND (which should ideally be performed by 12⁺⁶ weeks gestation)
• return data for the diagnosis/intervention standard SCT-S06: timeliness of PND
• make sure there are weekly failsafes in place to check screening is completed for all women who have accepted the test and that women are given their results

3. After screening test (diagnosis)

These requirements relate to the process of following-up screen positive results to get a confirmed result.

Providers must have systems in place to:

• maintain clear and accurate records of the woman’s or couple’s decision regarding whether they did or did not proceed with PND
• notify the maternity department screening coordinator and the woman’s GP of the woman’s or couple’s ‘at risk’ screening result if they decline PND
• send an alert card to notify the relevant newborn screening laboratory of the woman’s or couple’s ‘at risk’ screening result and their decision to decline PND (see ‘Appendix 7: at risk pregnancy alert form’ on Sickle cell and thalassaemia: screening handbook)
• make sure all women who are referred for PND are recorded
• notify the woman or couple of their PND results ≤5 working days of the PND test
• notify the appropriate healthcare services of the PND result
• return data for the referral standard SCT-S05: timely offer of PND (KPI ST4)

4. After screening test (intervention)

These requirements relate to the process of following-up people with a confirmed diagnosis and maximising the overall benefits from screening in terms of the final outcome to the person being screened.

Intervention and treatment

Providers must have systems in place to:

• keep a record of any PND results where the baby has the condition or is a carrier for the maternity or specialist counselling service to review after the baby’s birth
• offer information and counselling to all women or couples whose baby is found to have the condition
• support women who choose to continue their pregnancy and send an alert card to notify the relevant newborn screening laboratory of their PND result (see ‘Appendix 7: at risk pregnancy alert form’ on Sickle cell and thalassaemia: screening handbook)
• refer women for termination of pregnancy ≤5 days of the woman or couple making the decision and provide support
• record the pregnancy outcome
• return data for the intervention/treatment standard SCT-S09: timely follow-up, diagnosis and treatment
• make sure there are weekly failsafes in place to follow up all NBS results for babies who are high risk whether PND is accepted or not

Pathway outcome

Providers must have systems in place to:

• record outcomes data on the SCT newborn outcomes system for all babies who screen positive for SCT or who present clinically
• report screening outcomes to the National Congenital Anomaly and Rare Diseases Registration Service (NCARDRS)
• make sure the antenatal screening result is linked to the baby’s newborn blood spot screening result (and that the parental screening and PND results are included on the newborn blood spot card)