New tests to benefit rhesus negative pregnant women
The maternity department at NNUH is introducing a new test for rhesus negative pregnant women which will establish earlier in pregnancy whether they share their blood group with the baby they are carrying.
Women who have a rhesus negative blood type do not have a substance known as ‘D antigen’ on the surface of their red blood cells. In cases where these women do not share a blood group with their fetus, the woman’s immune system can develop antibodies against the rhesus (Rh) antigens carried by the baby causing potential harm.
To prevent this potential for harm, mothers are advised to receive an injection of anti-D, a treatment which prevents the production of these antibodies, at around 28 weeks of pregnancy and again shortly after birth, if the baby’s blood type has been established to be Rh positive. These injections can be painful and in some cases it can be necessary to administer further injections during the pregnancy because of sensitizing events.
Advances in laboratory technology mean that it is now possible to safely identify a baby’s blood type much earlier in pregnancy through a simple blood test, rather than waiting until the baby is born. The blood test will identify free fetal DNA from the baby in the mother’s blood and allow clinicians to understand whether or not women will require the anti-D treatment at this stage.
These developments will minimise unnecessary exposure to anti-D for pregnant women, as where it is definitively established that mother and baby share blood status, the injections will no longer be required.
Starting this week, the new tests will be available for rhesus-negative women as part of community midwifery services at around 12 weeks of pregnancy. The maternity team steering the innovation includes Screening Coordinator – Sister Alison Evans, Consultant Haematologist – Dr Hamish Lyall and Biomedical Scientist – Ms Deborah Asher.
Mr Alastair McKelvey, Consultant Obstetrician at NNUH, and another member of the team, said: “We’re delighted to be introducing this new service for pregnant women and believe our hospital to be the first in the region to be taking advantage of these technological developments to speed up blood type identification in pregnancy – saving women unnecessary discomfort and exposure to blood products. “
Around 6,000 women give birth at NNUH each year and this new service will benefit around 2,000 of those.
“The introduction of this facility has been a real team effort and I’d like to thank colleagues from across the midwifery and haematology specialties for bringing this project to fruition.”
Frances Bolger, NNUH Acting Chief Nurse, added: “Our maternity services receive great feedback from women regarding the quality of their care. This new service places us firmly at the forefront of clinical provision for women and is evidence of our ongoing commitment to use the latest innovations to enhance care.”