Disclosing to parents newborn carrier status identified by routine blood spot screening

No guidance is available on the best approach to disclosing to parents newborn carrier status inadvertently identified by routine newborn blood spot screening.

Newborn screening programs may inadvertently identify infants who are unaffected by serious in-born errors such as sickle cell disorders or cystic fibrosis, but who are genetic carriers. This will not affect the health of the child but may have important health, social and/emotional effects on the family. No trials were found about the impact or effects of disclosing newborn carrier status. There is an urgent need to develop clear guidance as how best to communicate this information effectively.

Authors' conclusions: 

There is a need to develop and evaluate the effects of interventions to support the disclosure of carrier status to parents following newborn screening.

In 2013 this review was declared 'no longer being updated'. See 'What's New'.

Read the full abstract...

Newborn blood spot screening programmes are designed to detect serious conditions affecting individuals, where early treatment can improve health. It is suggested that screening can improve the experience of diagnosis for parents. For example, without newborn screening, when a child with cystic fibrosis becomes symptomatic a period of uncertainty can arise prior to diagnosis. These potential advantages of screening need to be weighed against potential disadvantages of screening at individual and population levels. Some newborn screening programmes inadvertently identify newborn infants who, although not affected by the condition, carry a gene for it and can pass on that gene to their children; these are 'genetic carriers'. Knowledge of newborn carrier status can lead to: testing of parents and family members, and concern about possible affected future siblings should both parents be identified as carriers; the possibility of such testing revealing the putative father is not the biological father; concern about the child's future reproductive choices; and unjustified anxiety about the health of the carrier newborn.

There is an urgent need to develop clear guidance as to how to respond, with advances in technology fuelling the expansion of newborn blood spot screening and raised expectations of informed consent and disclosing test results. Depending on the condition for which screening is offered, options include: employing tests that do not identify carrier status, if available; identifying acceptable ways of disclosing carrier status; or identifying acceptable ways of not disclosing carrier status. These options are illustrated by screening programmes for sickle cell disorders and cystic fibrosis. Currently, there are no screening tests available for sickle cell disorders that do not identify carrier status. For cystic fibrosis, the policy choice is between an extended period of testing, and a screening result that is available sooner for most newborns, but inadvertently identifies carrier babies.


The aim of this review was to assess the impact of disclosing to parents newborn carrier status inadvertently identified by routine newborn blood spot screening.

Search strategy: 

We searched for reports addressing disclosing newborn carrier status to parents following newborn screening for sickle cell disorders and cystic fibrosis in: commercially available electronic databases (October 2002), specialist registers, online journals, online abstracts and conference abstracts. We also scanned the reference lists of included papers.

Selection criteria: 

Studies addressing the impact of disclosing carrier status using a soundly controlled trial or randomised controlled trial.

Data collection and analysis: 

Two researchers independently scanned titles and abstracts for relevance using the pre-specified inclusion criteria. Full reports of selected citations were then located and screened again for relevance by two researchers independently. At each stage, results were compared and discrepancies resolved by discussion.

Main results: 

We found no controlled trials about disclosing carrier status.