Are you “rhesus negative”? Have you been offered (or told you should have) the anti-D injection? Do you know that fetal rhesus testing is possible BEFORE your baby is born. If your baby is rhesus negative like you, anti-D is not needed. A baby inherits it’s blood type, including whether it is rhesus positive or rhesus negative, from it’s parents. If both are rhesus negative, baby cannot be rhesus positive.
If a woman has a rhesus negative blood group and is pregnant with a baby who has a rhesus positive blood group (inherited from the baby’s father or egg donor), her body can produce antibodies which damage the baby’s blood. In any subsequent pregnancy the reaction can get stronger, attacking the baby’s red blood cells. This is called haemolytic disease of the newborn (rhesus disease).
Many years ago it was discovered that this could be prevented by giving the woman injections of anti-D. Anti-D is made from donated blood and so is not acceptable to some people. Most people find the injection is uncomfortable and the injection site can be sore for several days. Some women will have side effects (headache, rashes or a mild fever) but occasionally a woman will have a major allergic reaction. Side effects are likely to increase with repeated doses. It is also a limited resource and should be used only when needed.
I am not against the use of anti-D. In fact I am very much in favour of it – when it is actually appropriate! When I first started working in healthcare we saw many babies who were anaemic at birth because of rhesus antibodies. We regularly needed to give newborn babies blood transfusions. Today this is rare, because anti-D can stop the formation of antibodies. What I am against is a blood product being given to many women who simply do not need it because both they and their baby have rhesus negative blood. Information about this test seems to have been slow to spread. Many of the information sources you may look at will not mention it.
Technology now exists to identify if your baby is rhesus positive or rhesus negative, from around 12 weeks gestation. If you have fetal rhesus testing and find that your baby is rhesus negative like you, you do not need anti-D. The test needs to be done before you have any anti-D, so early in pregnancy is advised. Read more here.
Back in 2016, NICE (National Institute for Clinical Excellence) advised that prenatal testing for fetal RHD genotype is recommended. Sadly many in many areas the NHS have still not started to offer fetal rhesus testing. While I was working in the NHS as specialist midwife for screening and fetal medicine in Surrey, I was able to introduce these tests as part of the pilot project. I have been frustrated by how slow it has been for this simple test to be made available across the country. In Sussex, Surrey and Kent these tests are still not offered as part of NHS maternity care in all hospitals.
After discussions with NHSBT, the national transfusion laboratory who offer fetal rhesus testing (RHD testing), I am delighted to be able to make it available to those who are willing to self fund the test. Your blood group is always checked at the start of pregnancy and I need to see a copy of that report. I then take a simple blood sample from your arm, which I send to the national lab. Results take about 2 weeks. If the test shows that your baby is rhesus negative, you should show that result to your maternity care provider and you will not require anti-D.
If you are in Sussex the inclusive fee for this test is £135 (including visit). A reduced fee applies if you are having other care with me. Read more here.
This test uses technology known as Non Invasive Prenatal Testing (NIPT). This is the same technology as is used for tests for Downs, Edwards and Patau’s syndromes, but the tests are quite different and separate. This can cause major confusion! The tests are done in totally different labs and one test cannot give the result for the other.
The wonderful Sarah Wickham has written a very accessible book about this subject if you want more detail