Newborn Screening - FAQs

  1. What does the treatment involve?

    The most important aspect of treatment for these disorders is dietary and special diets have been designed for each condition.  During periods of common childhood illness additional advice is given to parents and on rare occasions, admission to hospital may be needed.

  2. Could existing children be affected?

    As "genetic" conditions these disorders could affect existing or future children with the same parents.   In the event of a positive result, existing children would be checked and advice about future pregnancies offered.

  3. Does the test involve any risk?

    No additional blood sample is required and the only risk is the anxiety caused by a false positive result.   Like the conditions themselves false positive results are very rare so we anticipate around 28 true positive and 42 false positive cases from the 750,000 screened.   The chances of a false positive result is around 1 in 20,000.

  4. Can cases be missed?

    Yes, while most babies with these conditions will be detected by the programme it is possible that a baby with one of the conditions may not give a positive result.

  5. Is this “Research”?

    No, similar screening programmes are already undertaken in many countries throughout Europe and the USA.    This evaluation will not answer new research questions but will ensure that the way that the tests are conducted is carefully evaluated and optimised for use in the UK.   For the small number of cases which turn out to be positive, parents will be asked to participate in a research study to help improve treatment and evaluate the screening.

  6. What kind of additional disorders are being screened for?

    Five very rare disorders will be screened for (they are listed by name earlier in the leaflet). They typically occur in between 1 in 100,000 to 1 in 200,000 births, they all benefit from the early detection offered by screening.

  7. What causes these conditions?

    They are “genetic” disorders in which each parent, although well themselves, unavoidably passes the disorder to their child.

  8. What would happen if the baby’s test was positive?

    Positive results are extremely rare for these conditions. Parents will be contacted by telephone by the health professional concerned to check that the baby is well. An appointment will be made for the baby to be seen at a hospital for an assessment and some tests.   The results of these tests, usually available within 7 days, will either confirm the condition or indicate that the result was a false positive result.   In the meantime parents will be given advice about how to look after their baby and be given particular advice about feeding.   In rare circumstances the baby may have a brief stay in hospital.

  9. How effective is treatment and what would happen if the conditions were not detected?

    All these disorders are serious if untreated and while the baby seems to be well at birth can become ill. This can be very early in some cases or can take up to one or two years.

    Treatment started early is much more effective than delayed treatment.   In general when detected by screening the outlook for the affected baby is much improved although in rare cases even this can be ineffective.  Serious effects, including severe mental retardation or death may result if untreated.  

  10. Can parents and health professionals get further information?

    Further information on the pilot and the conditions to be included can be found at: