If routine blood tests have determined you and your baby might be Rh incompatible, your doctor may suggest a shot of Rh immunoglobulin, commonly known in the U.S by the brand name RhoGAM, during pregnancy and after delivery. While the term “Rh incompatibility” may sound serious, the treatment is simple and low-risk. Here’s what to expect if you need a RhoGAM shot.
What is the Rh factor?
If you’ve ever gotten a blood test or given blood, you probably noticed the “+” or “–” at the end of your blood type. This symbol indicates whether or not the Rh factor is in your bloodstream (O+ blood, for instance, has the Rh factor, while O- blood does not).
What is Rh incompatibility?
Rh incompatibility happens when an expecting mom is Rh-negative and her baby is Rh-positive. If your baby’s blood comes into contact with yours during pregnancy or delivery, your body can build antibodies against the Rh factor, which can lead to complications in later pregnancies.
What is RhoGAM?
RhoGAM is an injection your doctor will give to you in the muscle tissue of your arm or backside. It keeps your body from forming antibodies against the Rh factor.
Do I need the RhoGAM shot during pregnancy?
Your doctor will test your Rh factor early on in pregnancy; if you’re negative, he’ll also test your partner. If your partner is Rh-positive, your doctor will recommend you get the RhoGAM shot.
If you test Rh-positive, the shot isn't necessary.
When should I get the RhoGAM Shot?
If your doctor determines that you and your baby may be Rh-incompatible, you’ll get a shot of Rhogam during week 28 of pregnancy and then again within 72 hours after delivery to ensure that future pregnancies are as safe as the first.
If you undergo chorionic villus sampling (CVS) or amniocentesis, or if you experience bleeding during pregnancy or any trauma where you could be exposed to fetal cells, your doctor may give you the RhoGAM shot at another point in your pregnancy.
Do I need a RhoGAM shot after a miscarriage or a chemical pregnancy?
The RhoGAM shot is a preventative measure against any time a fetus’ blood supply comes into contact with yours, which can happen if you have a miscarriage or ectopic pregnancy — which is why your doctor may suggest a getting one if you test Rh-negative. You won’t, however, need a RhoGAM shot after a chemical pregnancy: It occurs so close to conception that Rh-factor is not yet present in a fertilized egg.
Are there risks or side effects of the RhoGAM shot?
The side effects associated with the RhoGAM shot are rare and mild. They may include:
- Soreness or rash at the infection site
- Mild fever
If you’re worried about the potential side effects, talk to your doctor about any concerns.
If you’re worried about getting RhoGAM because it is made from donated blood, keep in mind that there's no evidence that a disease like AIDS or hepatitis has ever been transmitted through the shot. Know that the shot has saved hundreds of thousands of moms’ and babies’ lives.
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