Antenatal blood group and antibody screen

Blood Transfusion

Purpose

All pregnant women should have a blood group and antibody screen performed during the first trimester, and a repeat taken routinely at 28 weeks gestation. This will confirm the woman’s blood group and identify if she is Rh D positive or Rh D negative, and if Rh D negative, the woman will be offered cffDNA testing and/or anti-D prophylaxis.

The antibody screen is repeated to check if the woman has any red cell antibodies which may cause HDFN. If red cell antibodies are detected, then additional samples may be required for referral to NHSBT Filton, Bristol for titre or quantitation, depending. The frequency will be determined by NHSBT.

Cord and maternal samples are required following delivery for an Rh D negative woman or women with red cell antibodies.

Notes

• All pregnant women should have a blood group and antibody screen performed during the first trimester
• A subsequent sample will be required at 28 weeks
• For RhD negative women a further sample will be required at delivery for possible Kleihauer test along with Cord Bloods
• For pregnant women with red cell antibodies, a further sample will be required at delivery along with cord bloods
• If Rh or other irregular blood group antibodies are detected, the sample may be referred to the NHSBT
• Any follow-up samples will be requested as required
• Performed at CGH and GRH
• The following factors are known to significantly affect the performance of the examination or the interpretation of the results: lipaemia, sample clotted (if EDTA), haemolysed. Any sample displaying these factors cannot be processed and will be rejected.

Sample requirements

EDTA tube -6ml

Required information

Sample and request form must be labelled correctly with 4 points of patient reference:

1. Forename
2. Surname
3. Date of birth
4. Unique Identification number

The sample and request form must be signed and dated by the person taking the blood sample.

Unlabelled, incorrectly labelled or inadequately labelled specimens will not be accepted. No specimen is considered unrepeatable.

Turnaround time

Within 24 hours.