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Rhesus Factor Compatibility to Avoid Miscarriage

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Rhesus factor and miscarriage

Are you aware that extra care is taken in pregnancy for women with a rhesus-negative blood group (O-, B-, AB-) because they are often prone to the risk of a miscarriage? Yes, that is just as closely related rhesus factor and miscarriage are.

For many years, most intending couple focus on the big genotype issue. Once the genotypes are compatible, they always feel they are good to go.

But tons of medical research has revealed that compatibility with a partner does not end with a compatible genotype only.

Ever known couples who take in, lose the pregnancy and find it almost impossible to have another baby again? Sure, at least one or two come to mind. Rhesus factor incompatibility remains one of the top reasons for such experience.

Rhesus factor compatibility
Source: Pexels

The big question is this: How much information do people really have about Rhesus factor and its implications on conception, pregnancy and miscarriage? Your guess is as good as ours.

If you read on, you will understand in clear terms the role of Rhesus factor and how it relates to pregnancy loss and the condition of future pregnancies.

Rhesus Factor Explained

Rhesus (Rh) factor is a type of protein found on the surface of red blood cells. A person is Rhesus-positive when they have this protein on their blood cells and Rhesus-negative when they do not.

The rhesus factor of a person is determined by their inherited genes, in the sense that they are passed from parents to offspring.

Thus, Rhesus-positive parents will likely have Rhesus-positive children. When either parent is Rh-positive or Rh-negative, the child will either be positive or negative.

It is important to note that a higher percentage of people are Rhesus-positive.

Nevertheless, the positivity or negativity of a person’s Rh is not supposed to be problematic to their wellbeing or detrimental to their health until it has to do with pregnancy.

This is where Rhesus incompatibility occurs when an expectant mother is rhesus-negative but carrying a rhesus-positive child.

Rhesus (Rh) Factor and Pregnancy

Rhesus factor compatibility
Source: Pexels

There is no risk involved when all parties are of the same rhesus type (either positive or negative).

However, when a rhesus-negative woman is pregnant with a rhesus-positive fetus from a rhesus-positive partner, there is a tendency of the woman’s system developing antibodies triggered by the blood cells from the fetus in the bloodstream either late in the pregnancy or even during delivery.

Antibodies are protein contained in the blood which the body develops in reaction to strange elements in the body to protect itself from infections.

Rhesus antibodies are triggered when the blood of the fetus comes in contact with that of the mother whose system recognizes as strange or odd thereby tries to destroy it.

Interestingly, this does not immediately affect the unborn child because antibodies do take time to build up. The real challenge begins with the future pregnancies (irrespective of if the first was carried full term, aborted or miscarried).

By this time, the antibodies are fully developed and can attack Rhesus-positive blood cells through the placenta causing a serious type of anemia to the new fetus and in turn leading to pregnancy loss.

Anemia results from the destruction of red blood cells at a rate faster than the body can replace them.

The red blood cells are very important because they are responsible for supplying oxygen to various parts of the body, without which the fetus will suffer and die (miscarriage).

Rhesus Factor Compatibility to Avoid Miscarriage

A miscarriage is not directly caused by just an expectant mother being Rhesus-negative. The risk of pregnancy loss comes only when the pregnant woman has been sensitized.

To be rhesus-factor sensitized implies that the expectant mother’s system had developed a reaction to the fetus’ blood cells. It is stated earlier that the Rhesus-negative mother develops antibodies that can attack Rhesus-positive blood cells through the placenta and cause serious anemia to the new fetus as a result of incompatibility.

Remember that the anemia usually does not affect the first Rhesus-positive pregnancy because the antibodies do take time to develop.

Future pregnancies are where the challenge comes in because at the stage, the antibodies are fully developed and automatically fights subsequent fetuses.

So, whether the first pregnancy was carried to full term or not, the following pregnancies will suffer the brunt.

Good News!

Rhesus factor compatibility
Source: Pexels

Thanks to advancement in medical science and health care, Rhesus-negative women should not be at risk for rhesus related miscarriages. An injection called RhoGAM (short form for Rh immunoglobulin or RhIg) has been invented to be routinely given to Rhesus-negative women to drastically reduce the risk of miscarriages.

The injection of RhoGAM contains antibodies that are embedded to the Rhesus-positive blood cells to avoid harm. This also stops the expectant mother’s system from its own antibodies that are detrimental to future pregnancies.

The major function of this medication is to stop the body from formulating such antibodies. RhoGAM shot is to be given to the expectant mother at the 28th week of pregnancy and if the baby is Rhesus-positive, the injection will be given again just after childbirth.

In the case of an abortion or a miscarriage, the RhoGAM injection is administered within three days.

Steps to Take

Rhesus factor compatibility
Source: Pexels

First and foremost, as a woman of child-bearing age, it is important that you pay attention to your rhesus blood type. Is it positive or negative?

You can find out your Rhesus factor by having a simple blood test at a good laboratory. Your rhesus status can be noted by checking for the sign (- or +) after your blood group. The major blood groups are – A, B, AB and O. Each of these groups can either be Rhesus-positive or Rhesus-negative.

For Rhesus-negative women, you can hinder the development of fetus-attacking antibodies by getting the RhoGAM injection. How the injection works has been carefully explained above. You just have to endeavor to ensure that treatment is given at the right time during or after pregnancy.

It is worthy to reiterate that the main goal of the treatment is to prevent the rhesus-negative expectant mother from developing antibodies that are problematic to the rhesus-positive fetus in the first place.

If you are a rhesus-negative woman, there is no cause for alarm. Kindly Speak to a Certified Ob/Gyn about your options and the best way forward. If you do not share the same Rhesus factor with your partner, Consulting a Health Provider is a step in the right direction as they will help you know whether you need the shot and when you should be given the injection.

NOTE that the injection is only very helpful if your body has not already developed the Rhesus antibodies.

Detecting rhesus incompatibility on time and taking the right medication will help you focus on other aspect of carrying your pregnancy to full term.

Congratulations on welcoming your healthy baby!

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Ginika Oluchi Okeke

Ginika is the Lead health writer at KompleteCare. She also doubles as an editor and proofreader for everything that concerns content. When she's not writing content for KompleteCare, you might find her copy-editing works for authors before publication.

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