Test to detect fetal cells in the maternal circulation following a sensitizing event. 

Transplacental or fetomaternal haemorrhage (FMH) may occur during pregnancy or at delivery and lead to immunisation to the Rh D antigen if the mother is D negative and the baby D positive. This can result in haemolytic disease of the fetus and newborn (HDN) in subsequent pregnancies. It is important to assess the volume of FMH to determine the dose of Anti-D immunoglobulin required by a Rh(D) negative woman to prevent sensitisation.

Sample type: Blood

Sample requirements: 

Pre delivery: 7.5ml EDTA maternal sample

Post delivery: 7.5ml EDTA maternal sample taken after a period of 30 minutes to 2 hours post delivery plus 7.5ml EDTA cord sample

- We understand that a full sample cannot always be obtained.  The laboratory will always try to test any sample but in some cases it may be necessary to request a new sample if the volume is insufficient for the test requested.  In such cases the requestor will be informed immediately.

In some cases, it may be necessary to request further samples in order to complete antibody investigations.  The laboratory will contact the requestor immediately if this is the case.

Ensure that sample tube expiry is checked prior to venepuncture.

Sample must be hand labelled and contain the following information:

  • Hospital number
  • Forename
  • Surname
  • Date of Birth
  • Patient location
  • Date and time of collection
  • Signature of collector

The request card must contain the following:

  • Hospital number
  • Forename
  • Surname
  • Date of birth
  • Sex
  • Patient location
  • Date and time of collection
  • Requesting Practitioner Signature (including medical officer/Midwives)
  • Name and signature of person taking sample (The name and signature should be completed in the box stating Patient ID checked and confirmed)

To minimise the risk of transcription error addressograph labels are encouraged to be used on the request card.

The request card should also be used to detail if the patient has any special requirements for transfusion, for example: Irradiated products

In addition for Antenatal requests (Green Antenatal blood form) please include:

  • Gravida
  • EDD
  • Date and dose or any recent anti-D prophylaxis

IMPORTANT: The Trust operates a zero tolerance policy.  Failure to observe the requirements for sample and request card labelling will result sample rejection and a repeat requested.

Sample validity: 72 hours at 2-8oC Samples should be sent to the laboratory immediately.  Improper storage of samples can lead to potential sample deterioration. Any samples which arrive in the laboratory 12 hours or more after venepunture will not be tested.

 

Turnaround time: 24 hours.