Fetal genotyping – diagnostic

Non-invasive fetal genotyping for mothers with red cell antibodies and non-invasive fetal sex typing

The IBGRL Molecular Diagnostics department offers United Kingdom Accreditation Service (UKAS) accredited fetal blood group genotyping tests to national and international customers.

The laboratory offers a non-invasive, convenient and reliable service for women who have red cell allo-antibodies and may be affected by haemolytic disease of the fetus and newborn (HDFN). Using cell free fetal DNA (cffDNA) in maternal blood, the fetal RhD, RhC, Rhc, RhE and K status can be predicted.

The laboratory also conducts a fetal sex genotyping service for pregnancies affected by X-linked genetic conditions or when early treatment of the fetus differs according to fetal gender.


International customers

The fetal genotyping test is available for customers (who do not have a Blood and Blood Component contract with NHSBT) under our Terms and Conditions contract by signing our referral form. Please contact our Business Development Manager Erika Rutherford erika.rutherford@nhsbt.nhs.uk for more information.

Sample requirements 

Investigation Notes Sample(s) required (minimum 0.5ml EDTA blood) Accompanying Form Turnaround times
Fetal Genotyping from Maternal Blood Pregnancy must be at least 16 weeks for RhD/C/E/c Pregnancy must be at least 20 weeks for Kell typing. 16ml EDTA blood per Rh test plus 3ml paternal blood if available (for RhD only) FRM4674

FRM4674 Guidance

Within 7 business days
Fetal Sex Typing from Maternal Blood Pregnancy must be at least 7 weeks. 16ml EDTA blood FRM4739

FRM4739 Guidance

Within 5 business days

Sending frozen plasma

Samples can also be sent as aliquots of frozen plasma prepared to a protocol provided by IBGRL – see INF1291. Please contact the laboratory prior to sending frozen plasma. Frozen plasma aliquots that do not meet the sample labelling requirements listed in INF1291 will not be tested.

Additional information

Technical aspects

Fetal Genotyping from Amniotic Fluid or Chorionic Villus

Investigation Notes Sample(s) required Accompanying Form Turnaround times
Fetal Genotyping from Amniotic Fluid or Chorionic Villus N/A 5ml Amniotic fluid

For CV send pre-extracted DNA (min conc of 10ng/µl & min volume 60µl)


FRM4738 Guidance

Within 10 business days

Amniotic fluid

To avoid the possibility of  contamination, it is preferable to dispatch the amniotic fluid without transferring it to a second container. If amniotic fluid is transferred from one container to another, then precautions should be taken to avoid contamination with material containing exogenous DNA. 

Chorionic Villus

Pre-extracted DNA must be referred. The laboratory performing the DNA extraction should ensure that procedures are in place to prevent contamination of the DNA samples with extraneous DNA or other substances. DNA must be at a minimum concentration of 10ng/µl and a minimum volume of 60µl.

More information on our services

User guide

Download our user guide for referring samples to IBGRL Molecular Diagnostics

Download guide (PDF)

Have a question?

Please contact the laboratory or our business development manager for more information:

If you wish to set up a contract to send samples or would like to obtain information regarding the tests performed, please contact Erika Rutherford.

For all other enquiries, please contact Molecular Diagnostics.