Health & Pregnancy

If you are Rh-sensitized, your doctor will watch your pregnancy carefully. You may have:

• Regular blood tests, to check the level of antibodies in your blood.
• Doppler ultrasound, to check blood flow to the baby?s brain. This can show anemia and how severe it is.
• Amniocentesis after 15 weeks, to check the baby?s blood type and Rh factor and to look for problems.

How is Rh sensitization prevented?

If you have Rh-negative blood but are not Rh-sensitized, your doctor will give you one or more shots of Rh immune globulin (such as RhoGAM). This prevents Rh sensitization in about 99 women out of 100 who use it.¹

You may get a shot of Rh immune globulin:

• If you have a test such as an amniocentesis.
• Around week 28 of your pregnancy.
• After delivery if your newborn is Rh-positive.

The shots only work for a short time, so you will need to repeat this treatment each time you get pregnant. (To prevent sensitization in future pregnancies, Rh immune globulin is also given when an Rh-negative woman has a miscarriage, abortion, or ectopic pregnancy.)

The shots won't work if you are already Rh-sensitized.

How is it treated?

If you are Rh-sensitized, you will have regular testing to see how your baby is doing. You may also need to see a doctor who specializes in high-risk pregnancies (a perinatologist).

Treatment of the baby is based on how severe the loss of red blood cells (anemia) is.

• If the baby?s anemia is mild, you will just have more testing than usual while you are pregnant. The baby may not need any special treatment after birth.
• If anemia is getting worse, it may be safest to deliver the baby early. After delivery, some babies need a blood transfusion or treatment for jaundice.
• For severe anemia, a baby can have a blood transfusion while still in the uterus. This can help keep the baby healthy until he or she is mature enough to be delivered. You will most likely have an early C-section, and the baby may need to have another blood transfusion right after birth.

In the past, Rh sensitization was often deadly for the baby. But improved testing and treatment mean that now most babies with Rh disease survive and do well after birth.

Frequently Asked Questions