Is the mother Rh Negative, the father Rh Positive? Is there any effect on the baby? (Rh Incompatibility)

Every mother and father feels incredibly happy when they find out that they are expecting a baby . But at the same time, a little fear also comes to mind, doesn't it? Questions like 'Will the baby be healthy?', 'Will everything be okay?' are running through your mind. Especially if your blood type is 'Negative' and your husband's blood type is 'Positive', you may have heard of something called 'Rh incompatibility'. Hearing this may make you a little scared. But don't worry at all. Let's talk about everything simply and clearly today.

What is the Rh factor?

Okay, first let's look at what this Rh factor is. It's very simple. It's a special protein on the surface of our red blood cells.

• If your red blood cells have this protein, your blood type is Rh Positive (+) . Like most people in Sri Lanka, the blood type of the majority of the world is Rh Positive.
• If you don't have this protein in your red blood cells, your blood type is Rh negative (-) .

A problem can only arise if the mother is Rh Negative and the baby is Rh Positive . If the mother is Rh Positive, there is no problem regardless of the baby's blood type. Similarly, if both the mother and the baby are Rh Negative, there is no problem there either. This condition does not harm the mother's health. The effect is on the baby.

How does incompatibility cause a problem?

This is very easy to understand. Normally, during pregnancy, the mother's and baby's blood do not mix. They are kept separate by the placenta.

However, during childbirth, especially when the placenta separates, a small amount of the baby's blood can enter the mother's bloodstream. Imagine this: the mother is Rh Negative. That means she doesn't have the Rh protein in her body. The baby is born Rh Positive. That means the baby has the Rh protein in its blood.

Now, when some of the baby's Rh positive blood enters the mother's body, the mother's immune system sees this Rh protein as a foreign, dangerous invader. Like a virus that causes disease. Then the mother's body starts making special soldiers, called `antibodies`, to fight against this 'invader'.

Since it takes a while for these antibodies to develop, the first baby is usually not harmed because this process begins after he or she is born.

If the second baby is Rh Positive, these antibodies from the mother's body attack the baby's red blood cells and begin to destroy them. We call this condition `Hemolytic Disease of the Newborn`.

What are the possible effects on the baby?

Because the mother's antibodies destroy the baby's red blood cells, the baby can develop various health problems.

• Anemia : The baby's blood volume decreases due to the destruction of red blood cells.
• Jaundice: A baby's skin and eyes turn yellow due to a substance called bilirubin, which is released from destroyed red blood cells.
• Serious conditions: In the most severe cases, the baby's organs, such as the heart and liver, may be damaged, and the baby may even die in the womb.

This is scary to hear. But the good news is that this situation can be very successfully prevented.

Solution: Anti-D (RhoGAM) vaccine

With the advancement of medical science, there is now a very effective solution to this Rh incompatibility problem. That is the vaccine called Anti-D immunoglobulin . This is commonly known by the brand name `RhoGAM`.

This vaccine is given according to a specific schedule.

1. Around 28 weeks of pregnancy: Almost all Rh negative mothers are given an Anti-D vaccine at this time. This is to avoid the very small chance of blood mixing in some way during pregnancy.

2. Within 72 hours of delivery: If the blood type of the newborn baby is confirmed to be Rh Positive, the mother will be given another Anti-D injection.

3. In other cases: This vaccine is mandatory after any event where the baby's blood may enter the mother's body, such as a miscarriage, tubal pregnancy, abortion, or amniocentesis.

The antibodies in this vaccine do not cross the placenta and do not harm the baby. Therefore, it is very safe.

A few more things to keep in mind

How is a baby's blood type determined?

If you are Rh Negative, your baby will definitely inherit an Rh Negative gene from you. Whether the baby is Rh Positive or Negative depends on the gene inherited from the father.

• If the father is Homozygous Positive (meaning he received Rh Positive genes from both of his parents), the baby will also receive a positive gene from him. Therefore , the baby will be 100% Rh Positive.
• If the father is Heterozygous Positive (meaning he has one positive gene and one negative gene), the baby has a 50% chance of receiving a positive gene and a 50% chance of receiving a negative gene. This means that the baby has a 50% chance of being Rh Positive.

Since these genetic issues are a bit complicated, you can talk to your doctor to explain this further.

Misconceptions and truth

Some people may be afraid of the Anti-D vaccine because it is made from blood. But these are manufactured after being thoroughly purified and proven to be safe. Also, you may hear stories like, "My friend had two healthy Rh Positive babies without taking Anti-D." Yes, it can happen very rarely. But it's like taking an unnecessary risk, like jumping into the street without looking for oncoming traffic.