Your doctor may have prescribed you to receive an Rh sensitization injection, or RhoGAM shot during pregnancy if you have an Rh-negative blood type. It’s an intramuscular injection prescribed to prevent Rh immunization in pregnant women (1). Continue reading to know about this injection and why a pregnant woman may require it. This post also discusses Rh sensitization and the key features of RhoGAM.

Why Does A Pregnant Woman Need RhoGAM?

If a mother (pregnant woman) is Rh-negative (the red blood cells lack the Rh protein) and the father is Rh-positive, then there are chances that the baby could be Rh-positive. In such a case, the mother, who is Rh-negative, will have to carry an Rh-positive baby. During pregnancy or delivery, small amounts of Rh-positive blood cells can enter the mother’s bloodstream. Since the mother’s body does not have the Rh protein, it will treat the Rh-positive blood as a foreign body and cause the body to produce antibodies to attack the red blood cells containing the Rh protein. If it is the mother’s first delivery, the produced Rh antibodies can cross the placenta and attack the Rh-positive red blood cells of the baby, increasing the risk of fetal anemia, miscarriage, stillbirth, or hemolytic disease (2). So, if your doctor finds such an Rh incompatibility during your pregnancy, then they might prescribe a RhoGAM injection that stops the mother’s body from producing antibodies to Rh-positive blood cells.

When Is RhoGAM Given During Pregnancy?

An Rh-negative blood type mother may need RhoGAM injection during the following conditions.

Within 72 hours of delivering an Rh-positive baby or for prevention of Rh immunization at 26 to 28 weeks of pregnancy.

Bleeding during pregnancy due to certain conditions.

Trauma to the abdomen during pregnancy.

After invasive procedures such as amniocentesis, CVS, fetal blood sampling, or fetal surgery.

Rh-negative women who could experience pregnancy loss at or up to 12 weeks of pregnancy. The dose is less.

Ectopic pregnancy (implantation occurring outside the uterus)

During attempts to manually turn a breech fetal position (3)

Can The RhoGAM Shot Cause A Miscarriage?

As per FDA, the RhoGAM injection belongs to pregnancy category C. There are no animal studies but the available human studies say that this injection does not harm the fetus or affect the pregnancy. It also does not alter the future reproductive capacity of the recipient (4). RhoGAM injection generally does not cause miscarriage; it is important to note that the risk of miscarriage is higher due to the Rh incompatibility than the injection. Once the mother’s body starts producing antibodies, all future pregnancies will be at risk (2).

Do You Have To Get The RhoGAM Shot In Every Pregnancy?

You need to get these shots in every pregnancy since they work for only a short while. Your doctor might give you one or more shots of Rh immunoglobulin during tests such as amniocentesis, around 28 weeks of your pregnancy, and after delivering your first Rh-positive newborn (5). Your doctor is the best person to determine the treatment.

Do You Need RhoGAM Shot After An Early Miscarriage/Abortion?

As per The American College of Obstetricians and Gynecologists, an Rh-negative mother can make antibodies even if her first pregnancy was not full-term (3). So, to prevent Rh incompatibility issues in future pregnancies, Rh immunoglobulin is given to an Rh-negative mother who has had a miscarriage, abortion, or an ectopic pregnancy (5).

Where Do You Inject RhoGAM?

The RhoGAM injection must only be administered intramuscularly (4).

Who Should Not Take RhoGAM Injections?

In the following cases, RhoGAM injections are contradicted (4).

Mothers who have a serious hypersensitivity reaction to human immunoglobulin products.

Mothers with a history of hypersensitivity reaction to RhoGAM and its components

IgA-deficient individuals since RhoGAM may trigger an allergic reaction.

Women who have hemolytic anemia or are at a high risk for hemolysis.

What Are The Side Effects Of RhoGAM Injection?

The RhoGAM injection is usually safe, but it may have some minor side effects such as:

Swelling, induration, redness, mild pain, or warmth around the injection site.

Sometimes, women may also develop skin rashes, body aches, or slight elevation in body temperature.

Your doctor will keep you in observation for 20 minutes after the administration to check if the injection has triggered any side effects (4).

What Happens If You Do Not Get RhoGam Shot When Pregnant?

If you do not take RhoGAM injection during pregnancy, then your body will start preparing antibodies for the Rh protein, which cannot be reversed. The antibodies might or might not affect your first pregnancy, but it will definitely cause adverse reactions for your subsequent pregnancies. In the absence of RhoGAM injection, your doctor may perform regular blood tests in the last trimester to see if you have become Rh sensitized, and if you have, then your baby will be monitored for adverse effects. If there is a serious problem, then you might have to deliver preterm (2). This post is for informational purposes only and is not a replacement for a doctor’s consultation. Do not use any medication without talking to your doctor.

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