Negative blood: main risks for the baby and what to do

When a woman has Rh negative blood and the baby has Rh positive blood, the mother’s body can react by producing antibodies that can increase the risk of the baby being born with anemia and, in the most serious cases, put his life at risk.

Most of the time, there are no complications during the first pregnancy, because antibodies only start to be produced when the woman comes into contact with the baby’s blood, which normally only happens during childbirth.

If you are concerned about the mother and baby’s blood type, it is recommended to consult an obstetrician. It is possible to prevent the production of antibodies against the baby’s blood when the mother receives an immunoglobulin injection during pregnancy. See more about the Rh factor.

What is the risk of Rh negative for the mother and positive for the baby?

The main risk of Rh-negative blood in the mother and positive blood in the baby is erythroblastosis fetalis, or hemolytic disease of the newborn. When this happens, the mother’s body produces antibodies against the baby’s blood, because it identifies it as a “foreign body”.

Due to the production of antibodies against the baby’s blood, the baby may develop anemia and have yellowish skin and eyes. Furthermore, in the most serious cases, it can affect the baby while still in the mother’s womb and put his life at risk. Learn more about fetal erythroblastosis and how to identify it.

To assess the risk of complications for your baby, make an appointment with the obstetrician closest to you:

Baby Blood Type Calculator

To find out the baby’s possible blood type and Rh, simply enter the mother’s and father’s blood type in the calculator below:

However, the baby’s blood type can only be confirmed through a blood test, which is sometimes indicated as soon as the baby is born, especially when there is a risk of incompatibility with the mother’s blood.

What to do to avoid complications

To avoid complications related to the mother and baby’s Rh, it is important to undergo prenatal care according to the doctor’s instructions, especially when the mother’s blood is negative and the father’s is positive, due to the risk of the baby’s blood also be positive.

Furthermore, when a woman is Rh negative and a man is Rh positive, the doctor may recommend blood tests to assess the risk of erythroblastosis fetalis. Therefore, when it is found that the mother does not yet produce antibodies against the baby’s blood, treatment with anti-D immunoglobulin can be carried out.

This treatment with anti-D immunoglobulin is normally carried out according to the following scheme:

• During the pregnancy: the injection of anti-D immunoglobulin is applied between the 28th and 34th week of pregnancy and up to 3 days after situations of risk of contact with the baby’s blood, such as abortion or threatened abortion and after amniocentesis or cordocentesis examination;
• After childbirth: If the baby is Rh positive, the mother must receive an anti-D immunoglobulin injection within 3 days of birth.

This treatment is generally carried out in each pregnancy in which the mother is Rh negative and there is a risk of having an Rh positive baby, but is normally not indicated if there are changes in the tests that indicate that the mother already produces antibodies that can affect the baby’s blood. baby.