Blood group and antibodies
This test tells us whether you belong to Group A, B, 0 or AB; whether your blood is Rhesus Positive (Rh +ve) or Rhesus Negative(Rh-ve)); and whether you have any antibodies (foreign blood proteins).
If you are Rhesus Negative, you will be offered blood tests to check for antibodies. If your baby has inherited the Rhesus Positive gene from its father, antibodies to the baby’s blood cells can develop in your blood. To prevent this happening, new guidelines now recommend that Anti-D be given, by injection, routinely to all Rhesus Negative mothers at 28 and 34 weeks of pregnancy. Anti-D should also be given to Rhesus Negative mothers whenever there is a chance of blood cells from the baby spilling into the mother’s blood stream (e.g. due to miscarriage, amniocentesis or CVS, vaginal bleeding, a blow to the abdomen and after the birth of the baby).