Rhesus Negative & Anti D
Posted on 23 October 2011
Rhesus Negative & Anti D
If you are rhesus negative you will have been informed at your booking in test (if you weren’t already aware). On its own this won’t make a difference to your pregnancy and birth.
However if you are carrying a rhesus positive baby then it can have implications.
What Does It Mean?
Rhesus positive ladies carry a protein called D antigen on their blood cells. Rhesus negative ladies do not have this antigen.
Usually rhesus positive babies have the antigen from their father.
The issue occurs when any of the (Rh positive) baby’s blood gets into the mother’s blood stream. The mother’s blood sees the D antigen as an invader and then creates antibodies to attack the baby’s blood. This is called sensitising.
This will not cause any problems at that particular time. The problem will occur in future pregnancies if the next baby is rhesus positive. The mothers blood will cross the placenta and attack the baby’s blood causing anaemia jaundice e or even heart and liver failure. This is known as haemolytic disease of the newborn.
So How Does Baby’s Blood Get Into Mums??
The biggest chance of blood crossing comes during childbirth, particular during instrumental births and caesareans.
But there also other occasions such as amniocentesis, during ectopic pregnancies, miscarriage, terminations or even during breech turning procedures such as ECV (external cephalic version).
Also a bang to your bump may cause a bleed.
So If You Can’t Be Sure When Baby’s Blood Has Caused Sensitising What Can You Do?
The key is to prevent sensitising in the first place and as you can’t predict when you may bash your bump then prevention is the best way. This prevention comes in the form of Anti D injections.
These injections contain immunoglobin which kills off any of baby’s blood that has got into Mums.
When Will I Get Anti D?
Blood tests during pregnancy can detect if any sensitising has happened and anti D will be administered if the results show that this has happened. However the injections are also given routinely at 28 weeks and sometimes at 34 weeks.
After baby is born they will check his/her rhesus status and if baby is rhesus positive then you will be given a further injection.
Anti D injections have been given since 1969 so is well practised and not unusual. If you are rhesus negative take good care x