Rhesus negative blood and pregnancy: What you need to know

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Rhesus factor (Rh) is an inherited protein found on the surface of red blood cells. If the blood has protein, you are Rh positive. If your blood has no protein, you are Rh negative. The "+" or "-" you have of your blood type refers to Rh positive or Rh negative.

Rh positive is much more common than Rh negative. Having an Rh negative blood type does not mean you have any disease and does not affect your health. But it can affect pregnancy.

Pregnancy needs special care if you have negative rhesus blood and your baby is rhesus positive. This is called rhesus incompatibility .

During pregnancy, problems can occur if you are Rh negative and the baby is Rh positive. Normally, the mother's blood does not mix with the baby's blood during pregnancy. However, a small amount of the baby's blood may come into contact with the mother's blood when the baby is born. It can also happen if you have bleeding or trauma to your abdomen during pregnancy.

If you are Rh negative and the baby is Rh positive, the body can produce proteins called Rh antibodies if your blood and the baby's blood mix. These antibodies are not a problem during the first pregnancy. But problems can happen if you get pregnant again.

If the future baby is Rh positive, the Rh antibodies can cross the placenta and damage the baby's red blood cells. This can lead to life-threatening anemia, a condition in which red blood cells are destroyed faster than the baby's body can replace them. Red blood cells are needed to deliver oxygen throughout the body.

If you are Rh negative, you may need to do another blood test - antibody check - several times: during the first trimester, during the 28th week of pregnancy and when the baby is born. Some people need the test more often.

This test is used to detect antibodies to Rh positive blood. If you have not started making Rh antibodies, you will likely need an injection (injection) of a blood product called Rh immunoglobulin. This prevents your body from making Rh antibodies during pregnancy.

If the child is born Rh negative, you do not need any other treatment. If the baby is born Rh positive, you will need another injection soon after birth.

In conclusion?

If you are Rh positive, you don't need to do anything.

If you are Rh negative and your baby is Rh positive, the body may produce antibodies that could be harmful during a second pregnancy. Do this:

- If you have vaginal bleeding at any time during pregnancy, contact your doctor immediately.

- Talk to the doctor about scheduling an injection of Rh immunoglobulin during pregnancy.

- Remind the medical team during delivery that you are Rh negative.