What is the test?
Carrier screening checks whether you carry a genetic variant for certain inherited conditions, such as cystic fibrosis, spinal muscular atrophy or haemoglobin disorders.
What does it assess?
Your carrier status. Carriers are usually healthy, but if both genetic parents carry a variant for the same recessive condition, a child may be affected.
Who might need it?
People with a family history of a genetic condition, certain ancestries, egg and sperm donors, and some people planning pregnancy or IVF who choose expanded screening.
When is it performed?
Ideally before pregnancy, so all reproductive options remain available.
How is the test carried out?
A blood or saliva sample is sent for genetic analysis. Panels range from a single condition to hundreds.
How should I prepare?
No special preparation. Genetic counselling before testing helps you understand what results could mean.
What can the results mean?
Most people carry at least one variant. What matters is whether both genetic parents carry variants for the same condition.
What are its limitations?
Screening cannot detect every variant or every condition, and a negative result reduces but doesn't remove risk.
Is it routinely recommended?
Targeted screening is used in selected circumstances and for donors. Expanded panels are optional and availability varies by country.
What happens next?
If both partners are carriers, a genetic counsellor can explain options such as PGT-M, donor gametes or prenatal testing.
Before paying for additional tests, read the HFEA Treatment Add-ons guidance.
Frequently asked questions
Is carrier screening on the NHS?
It is usually offered where there is a family history or known risk, rather than to everyone.